Maximizing loft is the true measure of synthetic sleeping bag design. Over time, all synthetic bags gradually lose loft due to stuff sack compression and general wear and tear. Designing a synthetic sleeping bag that would retain loft – and warmth – over the long haul became our engineering challenge, and our welded Lamina construction was born.
Welding stabilizes fill without sewing through the bag and pinching the insulation, thereby maximizing warmth and loft. Offset welds on the top and bottom of the bag increase fill stability.