Trek 900, 50°F Feather/Down Camping Mummy Sleeping Bag

50°F/10°C sleeping bag filled with feathers (down, 800 CUIN): high-end.1.5 lbs in size L:warm, light, compact. Mummy shape, yet comfortable. Ergonomic hood. Zipper with double slider. Water-repellent.

What are the limit temperatures for usage?

Limit temperature: temperature limit at which the user of the sleeping bag in huddled-up position is generally in thermal equilibrium and is neither cold nor hot (determined for a standard man under normal conditions of use). We recommend using an insulation mattress to optimize your thermal comfort.
This sleeping bag is filled with feathers and down. The thermal insulation may drop in damp conditions.

However, this is what you need to know about temperatures:

A sleeping bag does not produce heat but retains the heat produced by the body. If you are tired and cold and you slip inside a cold, damp sleeping bag, it is very likely that you will feel cold no matter how good your sleeping bag is! During the night, your thermal comfort will therefore depend not only on climatic conditions (humidity, wind, etc.) but also on your physical condition, your equipment (mattress, etc.) and your clothing (wool underwear, etc.)

For greater comfort, before getting into your sleeping bag:

Dress simply (1 layer of clothing is enough) Warm up your extremities: Use hats, gloves, socks, bed warmers, rubbing, etc.
A flask filled with hot water can be used as a foot or bed warmer (so long as there’s no chance of it opening by accident!)
Contract your muscles (70% of the energy consumed is converted into heat) but without making any movement generating a cold airstream. Use a silk or thermal sleeping bag liner to maximize warmth and hygiene inside your bag.

Shape:

• The mummy shape optimizes thermal insulation (no loss of heat because there is not much air flow or drafts) and saves space, which means that your movements are restricted.
• Width at the shoulders 28.7″, height at the feet 10.6″ in size L.
• Ergonomic hood with drawstring.
• Double slider, lined with an anti-cold duvet flap, side opening.
• X-shaped compartmented structure, through-stitching.

Weight and dimensions:

• Size S 1.2 lbs, user up to 5’3″ Bag dimensions: Ø 4.5″ x 13.4″. 3.5 liter volume. Weight 9.2 oz down.
• Size M 1.4 lbs, users from 5’3″ to 5’7″ tall. Bag dimensions: Ø 4.9″ x 13.4″. 4.2 liter volume. Weight 9.2 oz down.
• Size L 1.5 lbs, user from 5’7″ to 6′ tall. Bag dimensions: Ø 5.3″ x 13.4″. 4.9 liter volume. 10.6 oz of feathers.
• Size XL 1.7 lbs, user between 6’1″ and 6’9″ tall. Bag dimensions: Ø 5.7″ x 13.4″. 5.6 liter volume. Weight 12 oz down.
• Size and thermal insulation:

Try your sleeping bag before buying it to choose the right size for your comfort. Ideally, you should not be pressed up against the fabric, at the feet or head, and the fabric should not be taut. This would create thermal bridges that lower the insulation of your sleeping bag. Conversely, a sleeping bag that is too big will be harder to heat up and will not be as good at insulating the heat generated by the body.

Size and thermal insulation (continued):

• The weight, volumes, and sizes may vary slightly owing to production tolerances.
• Volume and dimensions in the bag may vary according to the compression applied to the product.

The fill power of down has 3 advantages for mountain sports:

• Thermal insulation provided by the air trapped in the down and feathers
• Ultra low weight: Down is lighter than synthetic fill while offering the same degree of warmth. This saves even more weight in your backpack
• Ultra-compressible

Care instructions

Machine wash on a delicate cycle at 86°F, wash inside out, with 3 or 4 washing balls (or clean used tennis balls). Use a detergent for feathers and down. Rinse multiple times. Spin dry on a slow and gentle cycle. Required step: Tumble dry on low heat on a delicate cycle. Finish off drying outside, ideally in the sun, on both sides to prevent the down from forming clumps. Dry thoroughly before storing.

Composition

• Filling: 90.0% Grey duck down, Filling : 10.0% Grey duck feather
• Lining: 100.0% Polyamide
• Shell: 100.0% Polyamide
• Carry bag: 85.0% Polyester cationic, Carry bag : 15.0% Polyurethane
• Bag cover: 100.0% Polyester cationic
• Optimal temperature: Comfort temperature 50°F/10°C, limit temperature 41°F/5°C
• Easy to transport: 1.5 lbs in size L. 4.9 liter volume. 2 bags: stuff bag and storage bag.
• Sleeping comfort: Comfortable mummy shape, ergonomic hood. Long zipper with double pull.
• Water repellent: Water-repellent fabric to optimize the thermal performance of your sleeping bag.
• Warmth: RDS ethical down and feathers with a fill power of 800 CUIN.