These are insulated chaps. They were invented/designed by a man in Anchorage, Alaska and were tested at Fort Richardson, AK. If it is cold enough to need long underwear in the morning, but too warm to still have them on by late morning, LEG JACKETS are the answer. Easy to put on or take off. Full-length two-way zippers and a 1" web belt with a side release buckle to put through your belt. They weigh 8 ounces per leg, and can stuff into a 6"x12" stuff sack.