At 820g this bag from Western Mountaineering will keep you warm in down to -7°C.

Great for hiking trips, cycling trips, mountaineering trips. You name it, this lightweight bag will keep you on the move and warm at night. 

Features:

• Full-length #5 YKK Zipper
• Full Down Collar
• 5 1/4 (13.5cm) Spacing/Continuous Baffles
• 59/38 (150cm/97cm) Shoulder/Foot Girth
• 5.5 (14cm) Loft, 20° F (-7°C)
• 16 oz. (455g) Down Fill
• 1 lb. 13 oz. (820g) Total Weight