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  • Marmot Atom Sleeping Bag: 40-Degree Down Open
  • Marmot Atom Sleeping Bag: 40-Degree Down Team Red/Redstone
  • Marmot Atom Sleeping Bag: 40-Degree Down Open

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  • Marmot Atom Sleeping Bag: 40-Degree Down Team Red/Redstone

Marmot Atom Sleeping Bag: 40-Degree Down

sale from $231.16 $308.95 20% off

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    • Sale Team Red/Redstone
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    1 Review


    Save some real weight.

    You could delude yourself into thinking that snapping your toothbrush in half and cutting the edges off your maps is actually going to save you some pack weight, or you could get the Marmot Atom 40 Degree Down Sleeping bag and actually save about two pounds. Being the lightest offering in Marmot's ultralight line, the Atom weighs a feathery one pound six ounces in the regular length, and maintains the lofty comfort you'd expect from a 800-fill down sleeping bag, so you'll stay warm as long as temperature hover above freezing.

    The Atom may be light, but it certainly isn't lacking in features. Sure, its Pertex Microlight fabric is light, but it's also breathable and water-resistant thanks to its DWR finish. The down fill has also been treated to repel moisture, so the fibers won't instantly clump and lose insulating properties if the bag should get wet. The Atom is available with either a left- or right-handed full-length zipper with an additional zip on the side, which creates a fold-down feature for those times you're sitting up in your bag, tent-bound and waiting for a storm to pass. To keep the Atom comfortable when it matters most, Marmot used a curved baffle construction to prevent down from wandering during your sleep adventures, and added an anatomic footbox to give your dogs some extra room to run around when you're dreaming about hiking.

    • 40-degree temperature rating
    • 800-fill down insulation
    • Down Defender water-resistant treatment
    • Pertex Microlight fabric with DWR
    • Mummy shape with anatomic footbox
    • Fold-down second zipper
    • Curved baffle construction
    • Stuff sack included
    • Item #MAR00T3

    Tech Specs

    Pertex Microlight (20D nylon ripstop), DWR finish
    800-fill down
    Max User Height
    [regular] 6 ft, [long] 6 ft 6 in
    Shoulder Circumference
    [regular] 61 in, [long] 63 in
    Hip Circumference
    [regular] 56 in, [long] 58 in
    Foot Circumference
    [regular] 39 in, [long] 41 in
    Bag Length
    [regular] 81 in, [long] 87 in
    Draft Tube
    Fill Weight
    [regular] 8.6 oz, [long] 10.5 oz
    40 F
    Stuff Sack
    Stuff Size
    6 x 12 in
    Claimed Weight
    1 lb 6 oz, 1 lb 8.5 oz
    Recommended Use
    backpacking, ultralight backpacking
    Manufacturer Warranty

    Tech Specs

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    Nice bag!

      I recently took this sleeping bag on a 6-day self-support kayak trip in Eastern Oregon. Size and weight were both critical and this product was perfect! When the temperature got down below freezing the bag was comfortable along with my lightweight down sweater. As we descended the canyon the air temperature warmed up and the bag alone was fine (night temperature around 38-40 degrees). This will be my go-to bag for ultralight trips in the future.