Western Mountaineering Bag Expander

Western Mountaineering Bag Expander is rated 5.0 out of 5 by 5.
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5 Star Rating
5.0
$60.00 - $75.00

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Product Details Specifications Ratings & Reviews Q & A Size Guide
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Product Description Item No.   10090172

The Western Mountaineering Bag Expander adds the extra space needed to your favorite Western Mountaineering sleeping bag. Do you have wide shoulders or sleep like a tornado? Never fear! You can now slide into your bag comfortably and roll around as you please with this handy bag expander. It makes the bag just wide enough for more comfort as you sleep.

FEATURES of the Western Mountaineering Bag Expander

  • Designed to coordinate with only Western Mountaineering sleeping bags
  • Instantly provides more space in sleeping bag
  • Great for creating extra room for warmer weather camping
  • Also allows you to squeeze into a Western Mountaineering sleeping bag with a snuggle buddy

- + Product Specifications
Best Use: Mountaineering and Alpine, Ultralight Backpacking, Backpacking
Bag Weight (Regular): 3.5 oz
Disclaimer: We only ship this brand to US Addresses.
Gender: Mens
Rated 5 out of 5 by from Worked great with my Alpinlite! I have wide shoulders and tend to toss and turn while I sleep so I’ve always had trouble sleeping well in a mummy bag. When I first got my Alpinlite it was a revelation. Now that I’ve added the expander as well, it’s even more comfortable. Was in the Emigrant Wilderness last weekend in the low 20s with 30mph wind gusts, and I was toasty and comfortable the whole night. For those that prefer extra comfort and sleeping through the night over adding 5.6oz, I highly recommend!
Date published: 2018-05-07
Rated 5 out of 5 by from Typical westernmoutaineering The quality does not disappoint! I’m 6’ 250lbs and it allows me to more comfortably fit into my Alder MF. All of their stuff is top of the line and this is no different!
Date published: 2018-02-02
Rated 5 out of 5 by from Great addition Adds a great deal of room to already great WM bags. Allows the addition of down jacket to boost warmth if needed. Well made like all WM gear.
Date published: 2015-10-16
Rated 5 out of 5 by from Western Mountaineering makes the finest gear on the planet! This exceeded what I expected, my last expander panel didn't even cover the full length of the zipper, COLD. The only thing I would like to see is a four season (this is three season) product. All in all this company makes top notch gear, you won't be disappointed. Thanks Moosejaw for carrying this!
Date published: 2014-12-23
Rated 5 out of 5 by from Works with my Montbell ULSS Down Bags Took a chance and bought the WM Bag Expander because it's half the weight of all the other brands. Needed it to squeeze my spoiled dog in my bag when the temps were too cold for her. Works like a charm. It's a little longer than my regular length Montbell bag but the zippers match so that's what matters. Don't know if it will work with other brands but it works for sure with the older models of the Montbell Ultralight Super Stretch Down bags.
Date published: 2013-04-04
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- + Size Guide

Sleeping Bags Size Comparison Charts

EXtremeLite Series Bags
Model Shape Size Shoulder Girth Hip Girth Foot Girth
MityLite Semi Rectangular 6' 3" 62" 59" 46"
HighLite Mummy Box Stitched 5' 6" 59" 51" 38"
6' 0" 59" 51" 38"
6' 6" 60" 52" 38"
SummerLite Mummy 5' 6" 59" 51" 38"
6' 0" 59" 51" 38"
6' 6" 60" 52" 38"
Tamarak Semi Rectangular 5' 0" n/a 58" 33"
MegaLite Mummy with Top Collar 5' 6" 63" 56" 39"
6' 0" 64" 55" 39"
6' 6" 65" 56" 39"
UltraLite Mummy with Full Collar 5' 6" 59" 51" 38"
6' 0" 59" 51" 38"
6' 6" 60" 52" 38"
AlpinLite Mummy with Full Collar 5' 6" 63" 56" 39"
6' 0" 64" 55" 39"
6' 6" 65" 56" 39"
VersaLite Mummy with Full Collar 5' 6" 62" 53" 39"
6' 0" 62" 53" 39"
6' 6" 63" 54" 39"
Microfiber Series Bags
Model Shape Size Shoulder Girth Hip Girth Foot Girth
Caribou MF Mummy Box Stitched 5' 6" 63" 56" 39"
6' 0" 64" 55" 39"
6' 6" 65" 56" 39"
Alder MF Semi Rectangular 6' 0" 62" 59" 46"
6' 6" 62" 59" 46"
Sycamore MF Semi Rectangular 6' 0" 62" 59" 46"
6' 6" 62" 59" 46"
Ponderosa MF Semi Rectangular 6' 0" 67" 64" 48"
6' 6" 67" 64" 48"
7' 0" 67" 64" 48"
Apache MF Mummy with Full Collar 5' 6" 59" 51" 38"
6' 0" 59" 51" 38"
6' 6" 60" 51" 38"
Badger MF Mummy with Full Collar 6' 0" 66" 57" 41"
6' 6" 67" 58" 41"
7' 0" 67" 58" 41"
Antelope MF Mummy with Full Collar 5' 6" 62" 53" 39"
6' 0" 62" 53" 39"
6' 6" 63" 54" 39"
Sequoia MF Semi Rectangular with Full Collar 6' 0" 66" 61" 48"
6' 6" 66" 61" 48"
Kodiak MF Mummy with Full Collar 6' 0" 66" 57" 41"
6' 6" 67" 58" 41"
7' 0" 67" 58" 41"
Bristlecone MF Semi Rectangular with Full Collar 6' 0" 69" 61" 48"
6' 6" 69" 61" 48"
Lynx MF Mummy with Full Collar 5' 6" 61" 54" 39"
6' 0" 62" 54" 39"
6' 6" 63" 55" 39"
Puma MF Mummy with Full Collar 5' 6" 62" 55" 39"
6' 0" 64" 56" 39"
6' 6" 66" 57" 39"
Gore Windstopper Series Bags
Model Shape Size Shoulder Girth Hip Girth Foot Girth
Apache GWS Mummy with Full Collar 5' 6" 59" 51" 38"
6' 0" 59" 51" 38"
6' 6" 60" 52" 38"
Badger GWS Mummy with Full Collar 6' 0" 66" 57" 41"
6' 6" 67" 58" 41"
7' 0" 67" 58" 41"
Antelope GWS Mummy with Full Collar 5' 6" 62" 53" 39"
6' 0" 62" 53" 39"
6' 6" 63" 54" 39"
Sequoia GWS Semi Rectangular with Full Collar 6' 0" 66" 61" 48"
6' 6" 66" 61" 48"
Kodiak GWS Mummy with Full Collar 6' 0" 66" 57" 41"
6' 6" 67" 58" 41"
7' 0" 67" 58" 41"
Lynx GWS Mummy with Full Collar 5' 6" 61" 54" 39"
6' 0" 62" 54" 39"
6' 6" 63" 55" 39"
Puma GWS Mummy with Full Collar 5' 6" 62" 55" 39"
6' 0" 64" 56" 39"
6' 6" 66" 57" 39"
Bison GWS Mummy with Full Collar 6' 0" 64" 55" 39"
6' 6" 64" 55" 39"