Big Agnes Anthracite Sleeping Bag 20°F | FireLine Pro Recycled, Slate, Long, Left Zip

Overview

Meet the Anthracite Sleeping Bag from Big Agnes — a 20-degree traditional down mummy bag built for hikers who want warmth without excess weight. It blends a contoured hood with a snug fit, while a left-side zipper allows pairing with a partner's bag when you are camping with a tentmate on cool nights.

On the trail: warmth, comfort, and practical design

Designed to maximize warmth-to-weight, the Anthracite keeps you cozy without slowing you down. The contoured hood and an oversized anti-draft collar work together to minimize drafts as temperatures dip. The insulated tube along the hood opening seals out drafts when cinched, and the no-draft zipper adds extra protection from chill. When nights are milder, the two-way anti-snag zipper invites easy ventilation and, if needed, a quick foot air out on warmer evenings. If you camp with a partner, mate left and right bags together to snuggle up for shared warmth.

• Lightweight performance with high thermal value and excellent packability
• Contoured hood and anti-draft features for a snug, draft-free feel
• Left-zip design suitable for pairing with a tentmate

Materials and sustainability

The shell and lining are soft and cozy GRS certified recycled polyester. FireLine Pro Eco insulation uses 100 percent post-consumer recycled polyester, delivering high loft to trap heat while maintaining a silky feel and compact packability.

• Recycled fabrics and insulation reduce environmental impact without compromising warmth
• High loft and compressibility help you stay comfortable in a compact pack

Specs and care

The Anthracite comes with a storage sack and a stuff sack, plus exterior loops for hang drying or storage. The Long size weighs 3 lb 1 oz, compresses to a footprint of 9 by 11 inches, and fits up to 6 ft 6 in.

Real-world use scenarios

Imagine a late-season summit push; a chilly alpine evening around the campfire; or a damp, breezy forest night where body heat matters more than the weather. The left zip configuration, draft protection, and reliable loft make it a versatile companion for many cool-to-mild outings.