Swim-sters special needs swim diapers are perfect for anyone who requires a diaper while swimming. They are designed to be worn discreetly under a swimsuit while helping prevent harmful from entering the water, so they are perfect for individuals with bowel incontinence. Testing results show that Swimsters effectively contain solids and help prevent harmful from entering the water. Sizing: XS-Size 6/8-Waist:17-24"; Weight: 40-58 pds. S-Size 8/10-Waist:18-27"; Weight: 59-74 pds. M-Size 10/12-Waist: 20-29"; Weight: 75-89 pds. L-Size 14/16-Waist: 21-32"; Weight: 90-118 pds. XL-Size 18/20-Waist: 22-34"; Weight: 119-141 pds.