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An ultralight, vest-compatible soft flask with integrated filtration, the UltraFlask+ 500ml lets you drink safely from natural water sources on the go.

An ultralight, vest-compatible soft flask with integrated filtration, the UltraFlask+ 500ml lets you drink safely from natural water sources on the go.

Hydrapak

Hydrapak Ultraflask+ 500ml Filter Kit Clear

£50.00
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Pre-Order

With Pre-Order, you can purchase the latest items added to our store in advance of them arriving with us.

Your Pre-Order is prioritised (at no additional charge); meaning that as soon as the product arrives with us, we can wrap it straight back up; ready for collection via Click & Collect or despatch to you — it often never even hits the stock room shelves!

Pre-Launch

With Pre-Launch, the date when we expect to receive the product ourselves is still a little too hazy to be confident in accepting Pre-Orders.

So, instead, you can submit your email address against the item you are interested in and we will email you as soon as stock arrives on the system.

Estimated Delivery & Collection Dates

Estimated Delivery & Collection Dates are given on Pre-Order and Pre-Launch products. They are for indication purposes only and can change at any time without notice.

The dates we provide are based on indications given by our suppliers. Whenever we get updated information from our suppliers we will endeavour to update the Estimated Delivery & Collection Dates provided on product pages.

We estimate this will be ready for despatch to you or collection via Click & Collect on Undetermined
Earn Rewards
When you purchase this item, you will earn of rewards points to spend on your next purchase from us. You can spend your Rewards balance in-store & online.

90-day returns period

We hope that you are perfectly happy with your order from Trekitt, but we understand that you may want to return your purchase. We offer a 90 days return period from the date of purchase, and endeavour to process all returns within 48 hours of receipt. During exceptionally busy periods, returns may take up to 7 working days to be processed.

We do not offer a free returns service. If using the DPD Returns Portal, a charge of £5 will be deducted from your refund when processed. Returns from Highlands and Islands using the DPD Returns Portal will deduct £15.50 from the order refund. Large DPD returns will have £6 deducted from their refund. (Specifications are over 5kg, and over Length of 30cm x width of 30cm and height of 10cm). If customers are returning items using their own postal service, and our returns form, all customers are responsible for any postage costs when returning any goods (excluding warranty returns).

For your convenience, follow here to the DPD Returns Portal to submit a return or click the button below. Alternatively, to arrange return postage for your items. Please use our warehouse returns address (Returns, Unit H&J, Moreton Business Park, Hereford, HR4 8DS) when completing the Returns PDF form below.


This is not a Trekitt operated service.

The Trekitt Returns Policy Includes...
A 90 day return period and the Trekitt 2-year Common Sense Guarantee.

Exemptions & Surcharges
PPE (Facemasks, Climbing Equipment etc. ), Food Goods, Accessory Cord, Socks & Underwear can only be returned if they have not been worn and/or removed from their original packaging with all swing tags still attached. If there is any sign or possibility that the goods have been used, tampered with or contaminated in any way, then we cannot accept a return on the grounds of consumer safety. Zips are typically not covered under a manufacturer's warranty.

Please take care when packaging your returning order as customers will be liable for any exceptions or surcharges incurred for incorrectly packaged returns. You will be informed via email of the value of the charges which will be deducted form your refund amount.

The above does not affect the Consumer Contract Regulations. Click here to read more.

I want to return/exchange an online order

To return an item to us, you must first:

  • Ensure the item is unused and in its original condition (including all label, tags and Boxes) and in a resellable condition
  • Complete our online returns request via DPD Returns Portal. Alternatively, to arrange return postage for your items. Please use our warehouse returns address (Returns, Unit H&J, Moreton Business Park, Hereford, HR4 8DS) when completing the Returns PDF form here.
  • Appropriately package your item in protective packaging, failure to do so will invalidate your rights to a full refund or return (including footwear boxes which can be damaged in transit/customer care if not protected)
  • Please take care when packaging your returning order as customers will be liable for any exceptions or surcharges incurred for incorrectly packaged returns. You will be informed via email of the value of the charges which will be deducted form your refund amount.

Trekitt Returns,
Unit H-J,
Moreton Business Park,
Hereford,
HR4 8DS

Please ensure the service you use corresponds to the size/weight/value of the item. We regret to inform you that we cannot be held responsible for returned goods that become lost or damaged in transit. We therefore strongly recommend that you use a recorded/insured delivery service and keep a record of this and track your item. Once it has arrived at our warehouse, please wait the advised 48 hours for your refund which you will be notified of with a refund receipt sent to your account email. If you have not heard anything after this then please reach out to our Customer Support Team [email protected].

You can also return internet purchases at the Trekitt Service Centre in Hereford. To speed things along, please bring the Sales Invoice we sent via email as proof of purchase.

If you choose to receive a refund, this will be processed separately by our Customer Support Team.

You may exchange product(s) at the shop for Goods of an equal or higher value for which you will receive a new receipt.

Please note:
PPE (Facemasks, Climbing Equipment), Food Goods, Socks & Underwear can only be returned if everything is exactly as it was received. Packaging and labelling must be intact, and underwear must be unworn. If there is any sign or possibility that the goods have been used, tampered with, or contaminated in any way then we regret that we are unable to accept a return on the grounds of consumer safety.

This does not affect Consumer Contract Regulations.

If you feel that your item is defective/broken/faulty and it is still under warranty, please contact our Customer Support team ([email protected]) with as much information as possible with regards to the fault, including photos if applicable.

In return, they will supply you with a Returns Authorisation Number (RAN), a Returns Form and a FREE postage label. Please complete the returns form with as much detail as possible and include it with your item.

Download our Returns Form.

Trekitt Returns,
Unit H-J,
Moreton Business Park,
Hereford,
HR4 8DS

We cannot make any decisions before inspecting any claim. Should the item be found genuinely faulty, we aim to reach a fair and agreed solution, which may be a refund, a replacement or a professional repair.

Please note: We may need to send items to the original supplier, or a fully certified testing company. This process can take up to four weeks or longer during busy periods.

THIS BIT IS IMPORTANT! - To ensure your Warranty Return goes smoothly, please ensure all items are in a clean, dry condition and free from dirt. Any items that do not meet the above criteria will be sent back to you for health and hygiene purposes or you may be contacted asking if you would like us to clean it for you, where a cleaning charge will be applied with a minimum charge of £25.00.

Failure to follow the Warranty Returns procedure may significantly affect our ability to process your return and cause a delay in issuing your refund/replacement/repair.

You can also return internet purchases at the Trekitt Service Centre in Hereford. To speed things along, please bring the Sales Invoice we sent via email as proof of purchase.

If you choose to receive a refund, this will be processed separately by our Customer Support Team.

You may exchange product(s) at the shop for Goods of an equal or higher value for which you will receive a new receipt.

We do not offer exchanges. Instead we ask you kindly to complete a new order for the desired replacement and return the unwanted Good(s) for a refund. We acknowledge that this might seem more complicated, we can assure you it is by far the most efficient and fastest way to ensure that you receive the goods you require.

Any returns sent back requesting an exchange will be refunded in line with our returns process.

You can exchange internet purchases at the Trekitt Service Centre in Hereford, to speed things along please remember to present the sales invoice supplied by us in respect of such Goods as proof of purchase. You may exchange product(s) at the shop for Goods of an equal or higher value for which you will receive a new receipt.

Book an appointment
When will I receive my refund?

Once our Returns Team has processed your refund, you will receive a new e-receipt showing the returned item(s). After this you should expect to see your funds back in your account within 3 to 5 working days, depending on how your card provider processes refunds.

Refunds can only be made to the original payment method and are normally processed within 2 working days, however, during busy periods they can take up to 7 days.

Once our Returns Team has processed your refund, you will receive a new e-receipt showing the returned item(s). After this you should expect to see your funds back in your PayPal account that same day.

Refunds can only be made to the original payment method and are normally processed within 48 hours, however, during busy periods they can take up to 7 days.

What is the Trekitt 2-year Common Sense Guarantee?

We love this business and take great care personally selecting the products we sell. We are confident that the kit we have chosen is the best currently available.

That is why we offer our Trekitt Common Sense 2-year guarantee on every product we sell!

Therefore, if within 2-years a manufacturing fault develops in the materials or construction of a product that we have sold you, we guarantee to sort it out. We aim to reach a fair and agreed solution, which may be a refund, replacement or a professional repair.

The "common sense" bit. Please don't send us kit that has been used and abused and is completely worn out, and then expect us to replace it. Stuff does wear out, it's a fact of life, however if you feel that your purchase is genuinely faulty please get in touch with us at [email protected]

Please note:
PPE (Facemasks, Climbing Equipment), Food Goods, Socks & Underwear can only be returned if everything is exactly as it was received. Packaging and labelling must be intact, and underwear must be unworn. If there is any sign or possibility that the goods have been used, tampered with, or contaminated in any way then we regret that we are unable to accept a return on the grounds of consumer safety.

This does not affect Consumer Contract Regulations.

What does "90 Day Returns Period" mean?

We offer an 90 Day returns period provided the items are returned in the original condition that you received them, including all labels and packaging intact.

Please note:
PPE (Facemasks, Climbing Equipment), Food Goods, Socks & Underwear can only be returned if everything is exactly as it was received. Packaging and labelling must be intact, and underwear must be unworn. If there is any sign or possibility that the goods have been used, tampered with, or contaminated in any way then we regret that we are unable to accept a return on the grounds of consumer safety.

This does not affect Consumer Contract Regulations.

Consumer Contract Regulations (CCR)

What are the Consumer Contract Regulations?

Under the "Consumer Contract Regulations, you have the right to cancel an order for goods made at a distance. These rights start from the moment you place your order and ends 14 days from the day you receive your goods.

Your right to cancel

Your right to cancel an order for goods starts the moment you place your order and ends 14 days from the day you receive your goods.

This 14 day period is the time you have to decide whether to cancel, you then have a further 14 days to actually send the goods back.

Your Right to a Refund under CCR

You may get a refund within 14 days of either, the trader getting the goods back, or you providing evidence of having returned the goods (for example, a proof of postage receipt from the post office), whichever is the sooner.

A deduction can be made if the value of the goods has been reduced as a result of you handling the goods more than was necessary. The extent to which you can handle the goods is the same as it would be if you were assessing them in a shop.

Refunding the cost of delivery

The trader has to refund the basic delivery cost of getting the goods to you in the first place, so if you opted for enhanced service e.g. guaranteed next day, it only has to refund the basic cost.

Exemptions

There are some circumstances where the Consumer Contracts Regulations does not give you a right to cancel. These include CDs, DVDs or software if you've broken the seal on the wrapping, perishable items and tailor-made or personalised items. They also include goods with a seal for health protection and hygiene reasons that have been broken or tampered with, e.g. Climbing Equipment and PPE.

My goods are broken

If you feel that your item is defective/broken/faulty and it is still under warranty, please contact our Customer Support team([email protected])with as much information as possible with regards to the fault, including photos if applicable.

We want to reduce our impact on the environment as much as possible, the first step for this is reducing our waste. Therefore, please note that we will always offer a professional repair in the first instance; if the product can be repaired.

This may involve your product being sent back to our suppliers or to a professional repair company. Please note that due tovaried procedures, warranty claims and repairs can take between 2 and 4 weeks to be concluded

Consumer Contract Regulations (CCR)

What are the Consumer Contract Regulations?

Under the "Consumer Contract Regulations, you have the right to cancel an order for goods made at a distance. These rights start from the moment you place your order and ends 14 days from the day you receive your goods.

Your right to cancel

Your right to cancel an order for goods starts the moment you place your order and ends 14 days from the day you receive your goods.

This 14 day period is the time you have to decide whether to cancel, you then have a further 14 days to actually send the goods back.

Your Right to a Refund under CCR

You may get a refund within 14 days of either, the trader getting the goods back, or you providing evidence of having returned the goods (for example, a proof of postage receipt from the post office), whichever is the sooner.

A deduction can be made if the value of the goods has been reduced as a result of you handling the goods more than was necessary. The extent to which you can handle the goods is the same as it would be if you were assessing them in a shop.

Refunding the cost of delivery

The trader has to refund the basic delivery cost of getting the goods to you in the first place, so if you opted for enhanced service e.g. guaranteed next day, it only has to refund the basic cost.

Exemptions

There are some circumstances where the Consumer Contracts Regulations does not give you a right to cancel. These include CDs, DVDs or software if you've broken the seal on the wrapping, perishable items and tailor-made or personalised items. They also include goods with a seal for health protection and hygiene reasons that have been broken or tampered with, e.g. Climbing Equipment and PPE.

Hydrapak Ultraflask+ 500ml Filter Kit Clear

Season:SS26

Brand:Hydrapak

Code:HYAH155F

What is the HydraPak UltraFlask+ 500ml?

The HydraPak UltraFlask+ 500ml is a smart evolution of the brand's signature running flask, now upgraded with an integrated filter that removes harmful bacteria and protozoa directly at the source. Designed for speed, safety, and simplicity, it allows you to refill and drink from streams, lakes, or taps without worry — eliminating the need for bulky bottles or external filtration systems. Its vest-compatible, low-profile design fits securely into most hydration vests and larger pack pockets, staying stable and bounce-free as you move.

What is it made of?

The UltraFlask+ is made of TPU, Silicone, POM, Hollow Fibre, and ABS, combining flexibility, filtration efficiency, and structural integrity in one lightweight design.

TPU Body with RF-Welded Seams

The soft, pliable TPU (thermoplastic polyurethane) construction allows the flask to collapse as you drink, reducing bulk and sloshing while maintaining durability against punctures and abrasion. Its RF-welded seams provide a watertight, long-lasting bond, ensuring leakproof reliability under trail conditions.

Reinforced Components and Secure Grip

Built with POM (polyoxymethylene) and ABS reinforcements, the UltraFlask+ maintains structure at the cap and neck for a stable, secure seal. The textured grip surface makes it easy to twist the filter on or off, even with wet or gloved hands.

Silicone Bite Valve for Smooth Flow

The soft silicone bite valve provides high-flow hydration and self-seals after each sip to prevent drips. Combined with the flexible TPU body, it ensures a smooth and consistent drinking experience without requiring excessive tipping or squeezing.

Safe, Taste-Free Hydration

Every component of the UltraFlask+ is made from BPA- and PVC-free materials, ensuring your water stays pure-tasting, odour-free, and completely safe — no matter how many times you refill it. Unlike cheaper plastics that can leach chemicals into your drink over time, HydraPak's advanced materials maintain water purity, even in hot or freezing conditions.

What are its features?

Fast and Safe Filtration

The integrated Hollow Fibre filter transforms the UltraFlask+ into a compact, self-contained purification system. It effectively removes 99.999% of E. coli and 99.9999% of Giardia and Cryptosporidium cysts, allowing you to safely drink from streams, rivers, and other natural water sources while on the move.

Despite its high filtration efficiency, the system maintains a fast flow rate of over 1 litre per minute, so you can hydrate without waiting or resorting to heavy pump filters. It's the ideal setup for fastpackers, ultra runners, or hikers covering big miles in remote areas — providing instant access to clean water without carrying excess weight.

Secure Grip

HydraPak's designers have added a flexible, contoured grip section to the flask, providing enhanced control while filling, refilling, or handling the filter. This textured surface ensures a firm hold, even with wet, sweaty, or gloved hands, reducing the risk of drops or cross-contamination when drawing from natural sources.

The grip also adds structure to the otherwise soft flask, making it easier to stabilise the bottle during backflushing or when attaching to a water filter or reservoir system.

Vest Pack Fit

Engineered for runners, fastpackers, and endurance athletes, the UltraFlask+™ is shaped to conform naturally to your body when tucked into a hydration vest or larger pack pocket. The soft TPU material flexes with your movement, preventing bounce or pressure points, while the slim profile ensures a stable and comfortable fit against the chest or side.

Once partially empty, the flask collapses neatly, maintaining its balance and reducing its bulk as the fluid level drops.

High-Flow Hydration

The self-sealing silicone bite valve delivers a smooth, high-flow stream of water that matches your effort, allowing you to drink easily without breaking your rhythm. Simply bite, sip, and release — the valve automatically seals to prevent drips or leaks.

The flexible valve material also feels soft and natural against the lips, ensuring comfort even during extended use.

Large Opening

Refilling the UltraFlask+ is quick and hassle-free thanks to its 42mm wide-mouth opening. The larger neck allows you to collect water easily from shallow streams or slow-moving sources, while also simplifying cleaning, drying, and attaching the filter.

The opening is compatible with most 42mm water filters and accessories, providing versatile options for various environments — from mountain streams to tap water refills at aid stations.

Compressible Design

Constructed from soft, durable TPU, the UltraFlask+ shrinks as you drink, reducing water movement and maintaining stability as you run or hike. This collapsible structure prevents sloshing, keeps weight closer to your centre of gravity, and ensures a balanced feel in your vest pocket.

Once empty, the flask rolls down to an ultra-compact size, taking up virtually no space in your pack.

Included Backflush Adapter

The included backflush adapter makes maintaining your filter simple and effective. It threads onto any HydraPak Stow bottle or compatible clean water source, allowing you to push clean water backwards through the filter to restore its original flow rate and prolong its lifespan.

Features:

  • Integrated Hollow Fibre filter removes bacteria and protozoa
  • Purifies up to 1,500L of water at >1L/min flow rate
  • 42mm wide-mouth opening for easy refills
  • Soft TPU construction with RF-welded seams
  • Compressible design eliminates slosh and bulk
  • Silicone bite valve self-seals after each sip
  • Textured grip for secure handling
  • Includes backflush adapter for filter maintenance
  • BPA- and PVC-free for clean, safe hydration
  • Compatible with most hydration vests and packs
Technical Information
Capacity: 500ml
Weight: 65g
Dimensions: 240mm x 70mm
Materials: TPU, Silicone, POM, Hollow Fibre, ABS
Colour: Clear
Filtration Capacity: ~1,500 L at >1L/min flow rate
Compatibility: Fits most vest pockets and 42mm filters
Sizing Information
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