Big Agnes Sidewinder SL Sleeping Bag

Price: $179.96
(as of Feb 06, 2026 04:20:49 UTC – Details)

Introduction to the Sidewinder SL Sleeping Bag

The Sidewinder SL sleeping bag is specifically designed for side sleepers, engineered to provide warmth, comfort, and ease of use in any position. Constructed with features from traditional mummy bags and additional body mapped insulation, this bag optimizes warmth and minimizes pressure points.

Features

• Ergonomic Design: The bag is contoured to ensure comfort and warmth for side sleepers, with a technical fit that moves with you as you roll from one side to the other.
• Body Mapped Insulation: Optimizes warmth where needed and reduces pressure points, ensuring a restful night’s sleep.
• Down and Synthetic Insulation: Combines the lofty warmth of down fill with the pressure point alleviation of synthetic insulation in the hips and feet.
• Thermally Efficient Footbox: Patterned to mimic the shape of your foot position while lying on your side, keeping feet warm.
• Jacket-Style Hood: Keeps insulation close to the body without sacrificing mobility, and can be cinched to seal out drafts.
• Pillow Barn: A unique feature made of stretch mesh material to keep your pillow in place, with interior access for easy adjustment.
• Smooth Zipper System: Features an anti-snag locking zipper and a long, ambidextrous zipper that stays out of your way when side sleeping.
• Storage and Hanging Options: Includes exterior loops for hang drying or storing the bag, along with a storage sack and stuff sack.

Pros

• Optimized for Side Sleepers: Designed from the ground up for comfort and warmth in side sleeping positions.
• Technical Features: Offers advanced features like body mapped insulation and a thermally efficient footbox for enhanced warmth and comfort.
• Versatile Insulation: Combines down and synthetic insulation for the best of both worlds in terms of warmth and pressure point relief.
• Lifetime Warranty: Backed by a lifetime warranty for durability and performance.
• Portable: Weighs just 2 lb. 7 oz. and packs down to 7 x 8 inches for easy carrying.

Cons

• Size Limitations: Designed to fit campers up to 5’5" / 165cm, which may limit its use for taller individuals.
• Specific Design: While optimized for side sleepers, the design may not be as comfortable for back or stomach sleepers due to its ergonomic contouring for side sleeping positions.
• Fill Weight and Materials: Although it features advanced materials, the fill weight and specific materials used may not be suitable for extreme cold weather conditions without additional layers or gear.

Specifications

• Face Fabric: Nylon ripstop for durability and resistance to tears.
• Fill: 650 fill DownTek for water repellency and insulating value, combined with FireLine ECO Synthetic Insulation for additional warmth and pressure point relief.
• Weight and Pack Size: Weighs 2 lb. 7 oz. and packs down to 7 x 8 inches.
• Dimensions: Fits campers up to 5’5" / 165cm, with a girth of 56”/142cm shoulder, 54”/137cm hip, and 31”/79cm footbox.