Sierra Designs Mobile Mummy 600 3-Season


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Who came first, the chicken or the egg? Was it Sierra…

Rating: rated 4 of 5 stars
Source: bought it used
Price Paid: $86 w/shipping as high bid on ebay used a few nights the fabric/tags crisp


Who came first, the chicken or the egg? Was it Sierra Designs or Exped? I dunno, but I like it. It's hard to say though whether it's an overstuffed extra long down vest or a warm roomy cocoon for human transformation, but it cries for transportation anywhere in camp.


  • Overstuffed with 600 hydrophobic down!
  • You can do all sorts of things with it not easy in a side zip bag
  • Silky fabric against the skin
  • In too warm weather just unzip and in colder zip up
  • Never snags zippers
  • Sierra Designs rockin' warranty


  • It's a pound heavier than my favored SD Nitro 800/20
  • I can't have it all in one bag, so I've got three down bags, two of which are SD's
  • It wasn't free, but it was a bargain

For me this design works the best, as I'm up and down numerous times during the night. With a side zip it works fine until it's colder. Then this bag shines, because I can just leave it on and unzip to satisfy the nature call.

I think I figured out the riddle and the answer is it's a roomy long cocoon meant for human transportation. The only ones better are SD's 800 fill lineup. I've got the Nitro 800/20 and it rocks. 

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Sierra Designs Mobile Mummy 600 3-Season

previously retailed for:
$129.95 - $349.95

The Sierra Designs Mobile Mummy 600 3-Season is not available from the stores we monitor. It was last seen February 24, 2018 at REI.

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