Cumulus Ultralight 350 (2012)

The Cumulus Ultralight 350 has a stripped-down ‘fast and light design’ that’s aimed at reducing pack weight and bulk. The commonly used trapezoidal baffle design is obvious on this model as the external stitch lines show the alternating narrow and wide faces of the baffles down the length of the bag. There is a full-length double-ended zip with an internal baffle featuring anti-snagging detailing and an external Velcro securing tab. The hood is quite a basic design and when cinched in it bunches up around your face a little. There’s no internal shoulder baffle so heat loss will be controlled by the hood adjustment, thus as with all the bags in the test it’s worth trying one out in the shop to see if the features suit you. The fit is slim on the Ultralight, especially in the leg area, where I found very little movement was possible. However the foot box was such that my feet had plenty of room and the down wasn’t compressed by movement, as was the case around my knees especially. The Ultralight has hanging loops and comes with a stuffsack and storage sack.

Weight (bag only) 804g
Size (length x shoulder width x foot width) 197x41x72cm
Packed size 12x27cm
Outer fabric Pertex Microlight
Inner fabric Pertex Microlight
Insulation 680 Polish goose down
Construction trapezoidal baffles
Comfort temperature rating n/a
Lower comfort limit -3 deg C
Extreme temperature rating n/a


The Cumulus Ultralight 350 is a very well-priced and warm sleeping bag thanks to its -3 deg C temp rating. Its basic design and slim fit will suit fast and light users with a relatively smaller frame; but at 804g it’s not the lightest option.

Review by Peter Macfarlane
First published in Trail magazine June 2012