Rab Alpine Pro 400 Sleeping Bag Celestial

Insulation: Starting with the most vital part of the bag, the insulation.  Rab use a high quality 650 fill power, R.D.S certified, hydrophobic, European duck down; we know there's a lot of info there so let's break it down.  

Fill power: refers to the 'fluffiness' of the down, therefore 1 ounce of this high quality down will fill 650 cubic inches of space when lofted fully. 

R.D.S: stands for Responsible Down Standard, ensuring the down comes from happy birds who haven't been live plucked and have been well cared for. 

Hydrophobic: refers to the coating that is applied to the down to allow it to perform better in damp conditions than untreated down. This coating will also ensure the down is warmer when wet, lofts faster and dries faster than untreated down.  

Outer fabric: Surrounding this high quality insulation is a Pertex Quantum Pro fabric; this fabric is water resistant, breathable, wind resistant and lightweight enough to allow the bag to pack down to a small size when not in use. Although you should never aim to allow a down sleeping bag to get wet, we know condensation and light drizzle are unavoidable, therefore this fabric prevents the down getting wet.  

If that wasn't enough of an information overload, Rab store the down in optimised trapezoidal chambers to increase warmth and decrease the likelihood of cold spots. These special shaped chambers allow the down to loft fully after being compressed for extended periods of time. As well as optimised chambers, Rab use “proportionally designed differential cut” which is basically the difference in size between the inner and the outer shell of the sleeping bag. Most inner shells will usually be the same size but the outer shell may need to increase to accommodate a higher weight of down or down of a higher fill power as you progress through a range of bags, for instance, a bag with an 800 fill power will have a roomier outer shell than a bag with a 600 fill power. 

A 3/4 length zip with a baffle behind prevents heat escaping through the zip, while an internal stash pocket stores items such as a phone or headtorch when the batteries need to stay warm. Included with the sleeping bag is a loft bag to store the sleeping bag when not in use, and a compression bag to (you guessed it) compress the bag in your pack when on the move. A 3D internal collar and hood drawcord ensure that all the lovely warm air inside the bag doesn’t escape. The fully insulated collar sits snugly around your shoulders to add an extra layer of protection and insulation in exceptionally cold conditions. The foot section features an angled which provides plenty of space without compressing the down and reducing warmth; no one likes cold feet!