About the Sac 2 The Sac 2 is the work horse of the Sac series, with a minus 2 comfort limit it is at home, in-house or in the out-house! All our synthetic sleeping bags have a first insulation layer of X-Static® fibre. These synthetic bags feature the very latest in sleeping bag technology; X-Static® silver fibre, 3D spiral fibre thermal barrier sheet and a woven suspension system. These bags are designed for general use and suitable for 3 season travel and camping. They will also suit warm sleepers who require something a little lighter. For more information please visit www.adventureone.com.au