Hotcore uses thermal body-mapping construction to place the insulation where it will do the most good. You already have an insulating sleeping mat below you, and most of the sleeping bag insulation that is below will be compressed by your body weight, making it inefficient. Hotcore moves much of this insulation to the top of our sleeping bags where it will trap warmth from your body.

Then Hotcore adds an extra layer of TrueLoft™ insulation in the core body area, from the neckline to below the beltline, to help achieve and maintain the temperature ratings. This extra layer of insulation will trap more warmth from the body than comparable sleeping bags, while adding very little to the weight, size, and cost of the sleeping bag. Think of it as putting on a jacket, the first thing we all do when we need to stay warm.

Hotcore calls this Critical Layer Construction.

High quality TrueLoft™ micro fibre synthetic insulation traps more warm air between its fibers than traditional insulations with the same loft. This gives you a warm, soft sleeping bag in a compact and lightweight size.

• Lightweight – some of the lightest weight insulation available
• Compressible – siliconized fibres slide easily allowing for greater loft, compressibility, and softness
• Breathable – insulation and fabrics breathe to allow heat-robbing moisture & humidity to escape
• Extremely quick drying – hydrophobic qualities allow TrueLoft™ to absorb less water and dry quickly
• Warm when wet – while drying, TrueLoft™ still keeps you warm, performing better than inferior insulations