A Q on traditional Japanese garb.?

There is a tight garment I have seen Japanese workersor ttravelerswearing in older films and prints. It encircles the waist from the lower ribs to the hips, I'm guessing to keep your back and/or abdomen warm. I have often seen it worn with no other upper body covering. It does not appear to be a wrap like an obi but could be. Does anyone know what I'm talking about and what its called?