Built with synthetic insulation and lightweight material typically reserved for a higher price point, the Synthesis packs light but hits heavy with its feature set. A dual zipper system makes getting in and out a breeze and gives you room to move about, while the self sealing foot vent lets you vent heat with ease.REGULAREN Limit Temp Rating: 41F / 5CEN Comfort Temp Rating: 49F / 9CFill Weight: 11oz / 311gMinimum Weight: 1lb 6oz / 626gFits Up To: 6' 0" / 183 cmLength: 76in / 193 cmShoulder Circumference: 62" / 152 cmHip Circumference: 56" / 142 cmFootbox Circumference: 40" / 102 cmMesh Stoarge Bag Size (LxW): 20 x 12" / 51 x 31 cmStuff Sack Size (L x W): 15 x 7.5" / 38 x 19cm LONGEN Limit Temp Rating: 41F / 5CEN Comfort Temp Rating: 49F / 9CFill Weight: 11.9oz / 337gMinimum Weight: 1lbs 8oz / 680gFits Up To: 6' 6" / 198 cmLength: 82in / 208 cmShoulder Circumference: 64" / 163 cmHip Circumference: 58" / 147 cmFootbox Circumference: 42" / 107 cmMesh Stoarge Bag Size (LxW): 20 x 12" / 51 x 31 cmStuff Sack Size (L x W): 15 x 7.5" / 38 x 19cm