Don't throw away that perfectly good towable cover, re-use it! TRL Watersports original replacement innertubes are quite simply the strongest in the business. If you need just the innertube and not the cover, then you have come to the right place! Breathe new life into your towable! Don't spoil that summer vacation by having your favorite towable "fall flat"! Have an affordable spare with you on your well-deserved time off! This is a bladder replacement for 80” diameter models like the O'Brien “Ultra Screamer”, XPS “Tsunami 3”, and White Knuckle “Skimmer” This is a replacement core bladder only, not the cover and will fit replace damaged bladders measuring 77-81" in diameter. If you have any questions on whether this innertube will fit your towable, we will be happy to assist and ensure it is compatible with your cover! Also available in 70”and 75” diameter class sizes. Thanks!!