Christmas Advent Calendar   |   Click to see today's offer


Osprey Stratos 50 Black

Osprey Stratos 50 Black

£105.00 £130.00
19% off

Customer Rewards points earned with this item.

Other colours available:
Osprey Stratos 50 Black

The Stratos 50 pack is all about ventilation and comfort, featuring an AirSpeed trampoline mesh back panel and Spacermesh shoulder straps and hip belt. Carrying this comfortable pack will literally be a breeze!


Season : 2019W OFFER

Code : 5420BLKBLK

Weight : 0KG

Hover over an icon to view more ...

What is the Stratos 50

The Stratos 50 is all about breathable comfort for multi-day camping, hut-to-hut adventures or day hiking with extra kit when the weather is changeable. It is the perfect for pack for any kind of walking or travel and thanks to the fully adjustable AirSpeed ventilated back system; carrying this pack will literally, be a breeze.

What is it made from?

The Osprey Stratos 50 is definitely built to last and uses tough, durable nylon fabrics to ensure it can soak up the bumps and scrapes of an active life. The main bulk of the bag is made from a super tough 210D Nylon Crosshatch with a durable water-repellent finish to keep your kit dry during light rain (a rain-cover is included for heavy downpours). This fabric is reassuringly thick, yet light enough that you barely realise you're wearing the pack, even when fully laden. Heavier and more durable 420D fabric is used on high wear areas such as the base and sides of the pack.

What is the back-system?

This is where the magic happens! Osprey have taken inspiration from their brilliant AntiGravity technology to create a seamless construction across the back-panel and hip-belt using highly breathable suspended mesh to create the AirSpeed Ventilated Trampoline Suspended back system.

This seamless and continuous construction method transfers weight superbly and is incredibly comfortable and lightweight. The whole pack is suspended away from the back-panel to produce an air gap that allows superb ventilation even on the hottest days. It won’t stop you sweating, but it will make you feel more comfortable.

The hip belt is reinforced with a die-cut foam to produce stability and control whilst allowing that ventilation theme to continue. It’s a well-padded hip belt that’s capable of dealing with the weight in the suggested load range of 12-18kg. It does an excellent job of transferring the loads to your hips and away from your shoulders.

The shoulder straps also feature die-cut foam for comfort, support and ventilation and flex beautifully around your body to increase comfort. You also get an adjustable sternum strap (with built-in whistle) to help spread the load.

Available in two different back lengths:

Small/Medium = 41-51cm

Medium/Large = 48-58cm

Each size of the AirSpeed back system is adjustable to ensure the perfect fit using a simple, yet highly effective, Velcro pad on the shoulder harness that can be easily set to various heights depending on the user. Please remember that your torso length and not your height will determine the back length. For example, I’m 191cm tall, yet only have a 47cm torso length, so my Osprey packs are all size Small/Medium. For more advice on pack fitting have a look at our video here.

Underpinning all that comfortable, breathable AirSpeed mesh is a flexible wire frame to transfer weight to the hips and to provide stability. The frame allows a degree of flex to the pack, so when you’re striding out, your shoulders can move independently of your hips.

What are the features?

It isn't just the comfort and support that we love about the Stratos 50, we also love the attention to detail and the number of clever, and unique, features.

The main entry point is through a traditional double-clip lid opening to give easy access to the pack’s contents. This style of opening arguably affords better weather protection and improved compression of the load. The top lid is extendable to provide extra storage if required, handy if you want to store a rope under the lid for scrambling or some via-ferrata. It can even be completely removed if not required to keep the pack weight to a minimum. A compression strap across the opening helps to secure that extra kit or keep the pack closed when the lid is removed.

In addition to the classic top loader opening, there’s a vertical side zip that enables you to access the contents without having to undo the top. This is really useful if you want to get at something at the bottom of your pack. The main compartment can also be split in two using the built-in divider and toggles. This creates a separate base compartment for wet or dirty kit, or to simply organise your pack more effectively. The base compartment can be accessed via a large zipped entrance at the bottom of the pack.

Inside the main compartment is a hydration sleeve with a little clip to stop the bladder from drooping down to the bottom of the sleeve. This is the perfect place to pop your Osprey Hydraulics reservoir.

Osprey equip the Stratos 50 with a single walking axe loop and the unique “Stow-on-the-go” trekking pole attachment system is a revelation. This allows you to safely stash your trekking poles away when they are no longer required without having to remove the pack or pester a mate to do it for you.

Four side compression straps pull the weight closer to your back, increasing comfort and carrying efficiency; they also stop gear from rolling about in a half full pack. The two at the bottom of the pack are called “InsideOut” straps as they can either be used inside, or outside the side pockets. Inside the pocket they compress the pack and not the pocket, and outside the pocket they secure the contents of the pocket and compress the pack. Simply thread the straps in the manner that suits your needs. Two further straps at base of the pack can be used for storing sleep mats or extra clothing; or can be completely removed if you just don’t need them.

Starting from the top, pockets wise, you get a zipped top lid pocket for quick access to kit that you need to get to easily, such as snacks and navigation equipment. Under the lid is a mesh pocket with an internal key clip, this is perfect for stuff you want to keep separated for safety and security.

The two mesh side pockets will easily take an insulating layer or a 1L bottle and feature a tougher fabric at the base to stop the mesh from being damaged by abrasion. There are two 3D zipped pockets on the hip belt that you can still gain access to even when the hip-belt is done up tight. 

On the front of the pack is a large stash pocket, the perfect place to store soggy waterproof clothing or even a wet flysheet. On the outside of the stash pocket is another large zipped pocket, giving you oodles of extra space.

Right down at the bottom of the pack is a small zipped pocket containing the rain-cover. This cover is tethered to stop it flying away in the wind, or it can be completely removed to shed a bit of weight in good weather. The cover fits snugly over the front of the pack and is held firm with an elastic drawcord.


The Stratos 50 features the perfect amount of space for multi-day camping trips, hut-to-hut adventures or loads of room for those who need to carry plenty of spare kit into the hills for the day. The traditional lid opening gives this pack a classic styling and improved weather resistance and the feature rich design and masses of pocket storage space make this a massively versatile pack.

  • Adjustable AirSpeed ventilated trampoline suspended mesh backpanel
  • Adjustable torso length
  • Base zip entry
  • Integrated & detachable raincover
  • Internal hydration sleeve
  • Internal key attachment clip
  • Removable sleeping pad straps
  • Side compression straps
  • Single ice axe loop
  • Single vertical zippered side access point
  • Sternum strap with emergency whistle
  • Stow-on-the-Go trekking pole attachment
  • Stretch front pocket
  • Top lid access
  • Twin zippered hip belt pockets
  • Ventilated stretch yoke and load lifters
Care & Advice

Getting the correct fit for your rucksack is as important as getting the fit right for your boots. A badly fitting pack can inflict misery and discomfort and completely ruin your adventure. This guide is designed to help you get the best fit and comfort from your chosen pack so that carrying all your kit becomes a pleasure and not a chore.


If the pack has an adjustable back length, adjust this to your correct level. Your back length is not related to your height but your torso length. Many packs, and specifically the bigger and more technical packs are available in different back lengths or feature adjustable back systems. Contrary to popular belief, your torso length and not your overall height is the key to getting a well fitted pack. Tall people don’t necessarily have long torsos, just as shorter people don’t always have a short torso length.

Your torso length can be found by measuring from your C7 vertebra (the bony protrusion at the back of your neck when looking down) to the height of your iliac crest (top of your hip bones, where you put your hands on your hips). This measurement will give you an idea of which pack back length to choose.

Once you've got the back length sorted, either by selecting the correct size pack or adjusting the back system, you can begin to follow these simple steps to help achieve a comfortable carry.


Before you start fitting the pack, loosen off all the straps as this will make it easier to get the correct tension later.


Fasten the backpack hipbelt, the general position is the same as where you’d put your ‘hands on hips’ This area is called the pelvic girdle, and what you can feel when you rest your hand on the area is the bony protuberance, the iliac crest. The iliac crest can support the weight from a pack comfortably, and for sustained periods. The padded section of the hipbelt should encompass this and fit securely.

Tighten the straps so the hipbelt feels secure and held firmly around your body. Ensure that the lumbar pad is centered to your lower back to give you maximum support. Remember that your hips carry most of the weight of the pack, so this should be firm but comfortable.


Next, adjust the shoulder straps, pull them until they start to become snug, but ensure that they are not too tight as to lift the pack off your hips. Remember tightening them will stabilise the pack but will increase pressure over the shoulders. If the back length of the pack is correct the shoulder straps will be flush to your shoulders whilst the hipbelt sits in place comfortably. The point where the shoulder straps attach to the main body of the pack should be roughly half way down your shoulder blades; this ensures  that the shoulder straps rolls evenly over the top of your shoulders to distribute the weight correctly.


Fasten the chest strap and pull until taut but not tight, the elastic section should not be extended. This helps keep the shoulder straps from catching in your shoulder joints and keeps the stability of the pack when moving over rough ground.


Top tensioner straps link the shoulder straps to the top of the pack. When tightened, their main function is to stabilise the top part of the pack. The optimum angle for these straps in 45º, but they will stabilise the load even when horizontal or at a more obtuse angle. Tighten them until you feel the top part of the pack rest against your pack, over tightening them will create excessive pressure on the front of your shoulders.


Side tension straps are linked to the hipbelt. By tightening these straps you can stabilise the load but reduce the hipbelt flexibility. Where balance is critical tightening them can help you feel more secure. However, if you are striding out over easy terrain it’s better to loosen these straps to allow full hip flexibility.


Side compression straps come next, pulling these tight does two things: firstly, it stabilises the load, secondly it can lift the lower part of the pack, repositioning the load closer to your back.


Following these steps should give you a comfortable but secure fit on your pack. Sometimes adjustments will need to be made on the go depending on the terrain or the load you are carrying. The perfect fit is very much a personal preference so experiment with different tensions on the pack to find what suits you best.

Technical Information

Fabrics: 210D Nylon Crosshatch / 420HD Nylon Packcloth

Size (S/M) - 47 Litres
Size (M/L) - 50 Litres

Weight (S/M) - 1.61kg
Weight (M/L) - 1.67kg

  • 4

    Osprey Stratos 50 Black ,  On

    Only used it on a practice yomp but seem very comfortable with a 10kg load. Plenty of adjustment for a good fit - trampoline back reduces the sweaty back problem. I will be getting a webbing trouser belt as my leather belt is too thick and tended to interfere with the rucksack waist harness. Overall very pleased
    YES Nick would recommend this item
  • 5

    Osprey Stratos 50 Black ,  On

    Perfect for what I was looking for. Very comfortable, adjustable and the ventilation system is excellent
    YES Ben would recommend this item
  • 5

    Osprey Stratos 50 Black ,  On

    I bought this to replace my old Lowe Alpine Airzone Pro 35:45. Gotta say, if the Osprey Atmos AG is the ultimate in comfort, then this Stratos 50 is only a fraction behind. Its very comfortable. The trampoline mesh back offers excellent ventilation with plenty of torso adjustment. Also, if you dont want your water bladder inside the pack, you could store it outside, behind the mesh panel. The Hip-Belt offers solid support & its pockets are a generous size. The Stratos 50 can be cinched down quite small and used as a less bulky day hiking pack but then has plenty of room for a weekend adventure. The lower sleeping bag compartment doesnt unzip to make one large space but the divider is like a large bellow, allowing you to fill from the top all the way to the bottom. Excellent! This pack does everything I need it to do. It weighs about 1.7 kg, so its roughly half a kilo heavier than the Exos and half a kilo lighter than the Atmos. My only concern is the side water bottle pockets are only mesh and may get ripped off Im not careful. Overall all, Osprey quality. Very happy.
    YES Rich would recommend this item
  • 3

    Osprey Stratos 50 Black ,  On

    Bought this as I was after something smaller and lighter than my current 65L rucksack. Only used once so far on a weekender so maybe a bit early for a review, but impressions so far. Pros: The suspension system/trampoline back - Osprey do this really well. Plenty of adjustment on torso length. Good cushioning on shoulder straps and hip belt. Weight - at 1.7 kg its much lighter than my previous packs. Full length side zip - probably more use to travellers than hikers. Cons: Front pocket not mesh or stretchy so not best suited for wet gear although there is a drain hole. No stretch to side pockets- seem a bit flimsy. Top lid attachment straps are fiddly and interfere with load lifter straps. Top lid is removable but no flap jacket as some of their other packs. Hip belt pockets very small and almost impossible to open or close one handed when hip belt is cinched. Overall impressions: None of the Cons are a deal breaker. A fairly decent pack that seems to be built down to a price.
    YES Reg would recommend this item
Write a review

Review This Item

As rated by 3 Customers

What do you think of Osprey Stratos 50 Black?

  • Your Forename
  • Your Email
  • How would you rate it?
  • Would You Recomend this product?
  • Yes: No:
  • Let others know your opinion.
  • Submit Review
Coming Soon

This product will be available very soon. Want to be the first to know when it arrives? Simply enter your email address below and we will notify you as soon as the stock is on the system


Thanks for choosing this item ...

Osprey Stratos 50 Black

Would you like to see the special offer we have for you?



"I first noticed Trekitt by their fantastic YouTube videos, which were very informative and honest. So I headed on over to the website and looked at various coats to try and determine which to go for. Being a bit of a muppet I didn't really have a clue what was best so contacted customer services who directed me to a few coats but said he would go away (over the weekend!) and think some more and get back to me Monday. I thought it was just a fob off as the conversation had been going a while but low and behold on Monday morning an email appears with suggestions! I was so pleasantly surprised that if I hadn't already been convinced to buy with them, it was concreted then. I bought 2 coats from them the same day and very shortly after they appeared. The fit was exactly as they had suggested it would be, the quality of the items was as described and I am very happy with them. In this day and age of large companies taking a backward step from customer service, it is such a breath of fresh air to be treated with such a personal touch. If I ever need anything outdoorsy, I know exactly where I'm going."

Piers  •  Oct 2019.

Read More Reviews

Need some help?
To improve your shopping experience today and in the future, this site uses cookies.
I Understand