In its stuff sack it is 538 cu. in. or 8.8 liters. With a compression sack it may compress some more. However it is a synthetic insulated bag which normally do not compress much like a down bag would.
Answered on 8/12/2013 3:19:17 PM by Prod. Spec. Kevin from Sierra Trading Post
Correction, the bag is 800 fill down per the product desription. Source: Product's website
"800 fill goose down with 90% down/10% feather"
Answered on 8/12/2013 4:06:41 PM by David from Vancouver, BC