These are nylon pants from Supreme. I purchased them about two years ago at Supreme Fukuoka. There are two white spots, one on the front and one on the left back, but otherwise, there are no noticeable stains. The white spots aren't very noticeable to me unless light hits them. There's a zippered pocket on the back, and the hem has a drawcord. These are now discontinued, so if you're interested, please consider them!