+Addaday Recovery Single Ball Massage Roller for Feet, Junior Model J, 3 Inches JUNIOR MUSCLE MASSAGER: Measures 3 inches in diameter to target and restore tired muscles so you can train harder than ever before. FOR FOOT & HEEL PAIN: Hold in hand or place on the ground and roll foot to help relieve heel, arch, and Plantar fasciitis pain. TRAVEL SIZE: This compact design can be easily stored in gym bags or totes. SOFT ROLLER: 3-inch soft roller is designed to knead muscles and help with scar tissue. SCIENTIFICALLY DESIGNED: Addaday rollers mimic techniques used by physical therapists to speed up muscle recovery and reduce the chance of sports or fitness related injuries.