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Sea to Summit Ascent ACI Down Sleeping Bag (-4C)

Sea to Summit Ascent ACI Down Sleeping Bag (-4C)
$459.00 - $489.00
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The Ascent™ down mummy sleeping bag redefines what versatile means in a sleep system. Complex construction and high-quality down keep you warm when it’s cold outside, while the triple-zipper Free-Flow Zip™ system ensures you stay cool and ventilated when the weather warms.

Shaped to allow a natural sleeping position for comfort, the Ascent is light and compact enough to go everywhere your adventures may take you.

Weight: 860g / 1.89lbs
Fill: 750+ Loft Ultra-Dry RDS Duck Down
Fill Weight: 330g /11.6oz

ULTRA-DRY Down 750+ Loft 90% Down Cluster Premium Duck Down certified Responsible Down Standard (RDS)

Free-flow zipper system: full-length YKK® #5 main side zip, half-length opposite side zip, and foot zip provides unparalleled ventilation and use as a comforter.

Vertical baffles over the chest to prevent down shifting as you roll over in your sleep.

Shaped hood, oversized draft collar, and zipper draft tube keep the cold out and the warmth in.

Internal pocket for phone / GPS / valuables.

Form a snug double sleeping bag by zipping to any Altitude™, Journey™ or Venture™ sleeping bag.

Includes lightweight Ultra-Sil™ compression bag and storage cell.

Bag Series
Ascent 1
Ascent 1
Bag Weight
1lb 14.3oz / 860g
2lbs 0.8oz / 930g
Compressed Volume
4.9 L
6.4 L
Compression Sack
S - 10L to 3.3L
S - 10L to 3.3L
Fill Weight
11.6oz / 330g
13.1oz / 370g
Fits Up To
6 ft / 183 cm
6 ft 6 in / 198 cm
Season Rating
2.5 Season
2.5 Season
25°F (Lower Limit)
25°F (Lower Limit)
Women's Temp
35°F (Comfort Limit)
35°F (Comfort Limit)


Sea to Summit Ascent Sleeping Bag

Be prepared for the unpredictable with our adaptable Ascent™ Series down sleeping bags. This range has everything you want for most adventures and then some. They’re lightweight, roomy, packable and surprisingly versatile.

Part Numbers

Option UPC MPN Store SKU
Regular 9327868095117 S1111 SLE529587971
Long 9327868095124 S1112 SLE533682691