For the alpinist looking for a lightweight, low bulk bag suitable for cold temperatures, the Neutrino 400 offers exceptional packability and warmth for its weight. Designed with a narrow mummy fit, for reduced bulk and pack size, and constructed with lightweight, high performance materials. It’s perfect for three season mountain missions. The Neutrino 400 is filled with 400g of 800FP, goose down, stabilized in chevron shaped baffles, cleverly designed to reduce the amount of fabric needed compared to traditional horizontal baffles. The trapezoid boxwall baffle construction allows the down to fully loft, eliminates cold spots, and maximizes warmth. Additional baffles along the length of the zip and around the neck decrease heat loss, and with an adjustable drawcord around the hood you can cinch the bag around your face. Now built with a recycled nylon lining and recycled Pertex® Quantum outer, it’s wind resistant and a little lighter on the planet too. The down is also finished with a Nikwax, fluorocarbon-free hydrophobic treatment for coping with condensation.

Weight saving chevron baffle design, reduces down migration and optimizes core warmth.
Trapezoidal boxwall construction with differential cut, to maximize loft and warmth
Close fitting adjustable neck baffle design for decreased heat loss
YKK 3/4 length main zip with synthetic filled baffle to trap warmth
YKK zipped internal stash pocket
Angled foot box for relaxed sleeping posture
YKK Anti-snag zip insert and anti snag internal zip guard
Hand-filled in Derbyshire UK
Zipped cotton sack with water-resistant base for home storage
Waterproof roll-top compression sack included
800FP European Goose Down with Nikwax Fluorocarbon-Free Hydrophobic Finish (400g / 14.1oz)
Main: 100% recycled polyamide - 20D Pertex® Quantum recycled nylon ripstop (38gsm) with fluorocarbon-free DWR
Lining: 100% recycled polyamide - 20D Recycled Nylon (38gsm)
Sleep Limit: 20°F (-7°C)
Sleep Comfort: 30°F (-1°C)
Sleeping Bag Length: 84.6 in
Max User Height: 6' 1" (72.8 in)
Internal Shoulder Girth: 70.9 in
Internal Hip Girth: 57.5 in
Internal Foot Girth: 43.3 in
Pack Size: 13.8 in x 9.1 in
Weight: 1 lb 14 oz (29.5 oz)