Sea to Summit Trek I 32 Degree 3 Season Down Sleeping Bag with Compression Sack Synthetic Down: ULTRA-DRYDown 650+ Loft 85% Down Cluster Premium Duck Dow Length / zip options: Regular - left or right zip Long - left zip Season ratings: Indoor/Summer Compressed volume: 5.1 Liters - Regular Compression bag: Small - 10 to 3.3 Liters