Western Mountaineering Alder MF

The semi-rectangular shape offers significantly more room in the shoulders and legs, making it ideal for side sleepers or anyone who feels restricted by the tight fit of a mummy bag. While you sacrifice a small amount of thermal efficiency compared to a tapered mummy, the extra space allows for more natural movement throughout the night.

Yes. The Alder MF features a full-length zipper system that allows you to open the bag completely flat. This makes it highly versatile for warmer nights where you want to use it as a top quilt or a standard comforter.

Yes, the zipper system is designed to be mated with other compatible Western Mountaineering bags. This is a great feature if you are camping with a partner and want to share warmth.

A 25F rating indicates the temperature at which the average person should remain comfortable, assuming they are using a sleeping pad with an appropriate R-value and wearing base layers. If you are a cold sleeper, you may want to add a sleeping bag liner or extra clothing to extend the bag's comfort range.

Continuous baffles allow you to shift the down insulation from the bottom of the bag to the top, or vice versa. This gives you control over where you want the most warmth, which is particularly useful if you are using the bag in warmer conditions and want to redistribute the down.