Ring hand grippers are made of silicone material directly washable that is odorless and latex free. The nonslip rings are also tear and crack resistant for long-term use. Each hand grip strengtheners has two different resistances. These 5 grip strengtheners includes 30 lb. 40 lb, 50 lb, 60 lb,70 lb, 80 bl rings. Progressive levels of resistance allows the difficulty of each workout to be gradually increased as your grip improves. Suitable for man, woman, seniors and teens who have different strength. Improve your marketing campaign with this colorful and customizable.