Useful, but the process is rather boring. And it is persistence. This is best done in summer. I forgot the specific reason. Probably the hot weather has a good effect on blood circulation block. It's best after a hot bath. Apply hot compress to your legs first, then massage with essential oil for a while before shaving. Douban, someone made a comparison of scraping effect by themselves. Obviously. If the landlord is patient, this is a good way. Especially muscle legs that are useless for exercise.