Primaloft
Primaloft is a soft and compressible synthetic fibre commonly used to insulate clothing and accessories. Although not quite as warm for its weight as down insulation, Primaloft maintains its loft when wet so is often more suitable for use in damp or wet conditions.
Fill Power
Down fill power is not used to indicate how warm a product is, but as a measure of how warm a certain weight of actual down is. Basically, the higher the fill power the better quality and more efficient the down. 500 - 600 fill power is pretty good, 600 - 700 is excellent, 700 - 800 is better still and anything above 850 fill power would indicate exceptional quality down.
Pile Fleece
Pile is a very warm and durable version of synthetic fleece. It’s often one-sided and therefore used as a liner in jacket, hats and gloves. The fibres are long and stand on-end to trap a lot of heat. Pile fleece also tends to wick moisture very well and maintain its warmth when wet.