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  • Western Mountaineering - Sonora Sleeping Bag Liner - One Color
  • Western Mountaineering - Sonora Sleeping Bag Liner - One Color
  • Western Mountaineering - Sonora Sleeping Bag Liner - One Color

Current Color

  • Western Mountaineering - Sonora Sleeping Bag Liner - One Color
  • Western Mountaineering - Sonora Sleeping Bag Liner - One Color
  • Western Mountaineering - Sonora Sleeping Bag Liner - One Color

Western Mountaineering Sonora Sleeping Bag Liner

$42.00 - $52.00

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    • One Color, Mummy Regular
    • One Color, Taper Regular
    • One Color, Mummy Long

    4 Reviews


    Think of it as your bed sheet.

    Cozy into Western Mountaineering's Sonora Sleeping Bag Liner at night, and you might think you're waking up in your bed even though you're camping. This liner's polyester construction feels as soft as your bed sheet back home, and it adds warmth if you're too cold and moisture management if you're too warm. This liner is machine washable so it doesn't smell like last trip's campfire, and Western Mountaineering included a stuff sack so you can take it backpacking. 
    • Sleeping bag liner adds warmth and comfort to cold camping trips
    • Polyester construction ensures softness and moisture management
    • Machine washable keeps each trip fresh
    • Included stuff sack for convenient packing
    • Item #WES001B

    Tech Specs

    100% polyester
    mummy, rectangular, semi-rectangular
    [mummy, regular] 72in [regular taper] 78in
    Claimed Weight
    [mummy, regular] 5oz [regular taper] 6oz
    Recommended Use
    camping, backpacking
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Update After PCT

    • Familiarity: I've put it through the wringer

    I took this liner on the PCT this year and its the best liner out there. The main reason I took this liner was to protect my Western Mountaineering Versalite because after hiking 15-30 miles a day you get real sweaty and gross and if you hop in your sleeping bag without either showering or having a liner it'll decrease the life of the bag tremendously. I bought a $700 bag for a reason because it'll last a lifetime. And with this liner, it'll last that lifetime looking ( and smelling ) a lot cleaner, and warmer as when down gets dirty ( from sweat and grim on you when you get in it ) it'll lose its loft and in the world of insulation loft is warmth. So I choose to spend a little extra money and weight to have my bag work as it's supposed to. Another plus to having a liner on a thru-hike is you now have a laundry bag when you need to wash your clothes in town. As well as washing the liner which will, in turn, keep the sleeping bag cleaner. Its a no brainer to me to have a sleeping bag liner. It also adds a couple of degrees of warmth which is always a bonus on those chilly nights. I'll continue using this any time I use a sleeping bag.

    Picture: If you use a liner and keep it dry your bag will be just as lofty even after 100+ nights in it.

    Update After PCT

    Keeps the bag clean

    • Familiarity: I've put it through the wringer

    This Liner is way comfy and keeps my sleeping bag clean. It also packs down super small so I take it everywhere! It's western Mountaineerings usual sewing, which is super well done and I'm expecting this liner to last a long time.

    Spencer - thank you for this. I don't think how much "keeping your bag clean" really adds to the life of the bag. It's part of the care and feeding of a Western Mountaineering bag, or any down product for that matter. As you know, when down gets oily form our body, the down does not have the ability to loft as well, and so it looses warmth. Loft = Warmth!

    Thanks again for writing and enjoy your bag!

    Western Mountaineering Rep

    Seriously Added Warmth

    • Familiarity: I've used it once or twice and have initial impressions

    I've had this for almost a year now, and I finally got the chance to use it and boy, it sure does the job it claims it will. I have the Alder 25 degree bag and the forecast was for temps down to 12 degrees, so I busted this liner out and put it to use. First off, its very soft and felt more like a nice bed sheet than anything else. But the more impressive part was how comfortable I felt through the whole night while it got down to about 10 degrees outside the tent while I was nice and toasty inside this liner and my 25 degree bag. I thought for sure it hadn't gotten as cold as forecasted, but my frozen water bottle next to me and the thermometer on my watch I hung on the outside of my tent confirmed that it had indeed!

    Unanswered Question

    Could you please tell me what degree of warmth this product might add.