Description With minimal pack size and weight, it can be easily stowed until needed. Combine with a windproof layer such as waterproof cap or hood to effectively trap body heat. PRIMALOFT® ACTIVE Blurring the line between wadding insulation and fabric PrimaLoft® ACTIVE loosely weaves PrimaLoft® s industry leading insulating fibres through a fine polyester mesh. The resultant structure is warmer and less than half the weight of a conventional fleece product – Down like performance when dry whilst also still performing when wet.