Traditionally fused thermal clothing.
Slightly curved collar with inner rib that fits tightly to the neck and keeps the cold out.
Extra protection against the cold with an extended back.
Elastic in arm hole.
Inside chest pocket.
Ultrasound welded polyester with insulating polyester wadding. Slightly curved collar with inner rib that closes tightly to the neck and keeps the cold out. Zip right through. Extended back. Elastic in arm hole. Internal chest pocket.