Kelty Cosmic 0 Degree 550 Down Sleeping Bag

A proven classic built to keep you warm. The Cosmic Down Sleeping Bag has earned its reputation as a three-season favorite thanks to smart design, reliable warmth, and durable, eco-conscious materials. Its trapezoidal baffle construction—yes, that trapezoid from geometry class—helps trap heat more efficiently, keeping you warmer when temperatures drop.

Insulated with lightweight 550-fill down and wrapped in fully recycled fabrics with a PFAS-free DWR treatment, the Cosmic Down balances warmth, packability, and sustainability. An expanded natural-fit footbox gives your feet room to relax, while a full draft tube and collar seal in heat for added comfort.

From campsite nights to shoulder-season adventures, this sleeping bag delivers dependable performance with thoughtful details that make a real difference.

Best For

• Three-season camping and backpacking
• Cold-weather shoulder seasons
• Campers who want warmth without a mummy-tight fit

Key Features

• Trapezoidal Baffle Construction: Improves thermal efficiency and heat retention.
• 550 Fill Down Insulation: Lofty, lightweight, and warm.
• Recycled Fabrics: Fully recycled shell and liner with PFAS-free DWR for water resistance.
• Heat-Retaining Design: Full draft tube and draft collar help prevent heat loss.
• Anti-Snag Zipper: Quad-stitch construction makes entry and exit smooth and easy.
• Ventilation Control: Dual locking sliders allow customizable venting.
• Natural-Fit Footbox: Expanded shape provides more room to move and sleep comfortably.
• Internal Stash Pocket: Zippered pocket keeps small essentials close.
• Stuff Sack Included: Makes packing up quick and easy.

Construction & Materials

• Insulation: 550-fill down
• Shell Fabric: Recycled 20D nylon taffeta
• Liner Fabric: Recycled 50D polyester taffeta

Specifications (All Sizes)

• Temperature Rating: 0°F / -10°C Tested at 5°F / -15°C
• Bag Shape: Semi-rectangular

Size & Fit

Regular

• Fits up to: 6'0" / 183 cm
• Weight: 4.34 lb / 1.93 kg
• Fill Weight: 39.5 oz / 1120 g
• Length: 78 in / 199 cm
• Shoulder Circumference: 62 in / 158 cm
• Hip Circumference: 57 in / 147 cm
• Foot Circumference: 46 in / 117 cm
• Stuff Sack Size: 10" × 19" / 25 × 48 cm

Long

• Fits up to: 6'6" / 198 cm
• Weight: 4.5 lb / 2.04 kg
• Fill Weight: 41.6 oz / 1178 g
• Length: 84 in / 214 cm
• Shoulder Circumference: 64 in / 163 cm
• Hip Circumference: 60 in / 152 cm
• Foot Circumference: 52 in / 131 cm
• Stuff Sack Size: 10" × 18" / 25 × 48 cm