Rad Dog Release N Run Dog Leash and Collar | Walking, Hiking, Running | Built-In Retractable Leash, Dogs Up To 100lbs, Durable Nylon Collar | Live Un-Leashed! CONVENIENT LEASH FOR THE OFF-LEASH DOG: Just let go of the leash and it fully retracts into the collar. Designed for the mostly-off-leash dog! SUPER STRONG COLLAR & CORD: The Release N Run collar is made from durable nylon webbing -- the same stuff climbers use. The Release N Run cord looks skinny, but it's made from Spectra by Honeywell, one of the world's strongest and lightest fibers. DURABLE MECHANISM & COVER: The internal retracting mechanism was originally designed for extended use in salt water by scuba divers and the military. The cover is burly Cordura -- rough play or travel through dense brush won't phase it. MADE IN THE USA: Rad Dog products are all manufactured in Bellingham, WA. IDEAL USES: Running, Hiking, Backpacking, Walking, Dog Park. SIZING: See size chart for sizing info.