Description Hoses are made to be an exact fitment like OEM, but with additional strength to reduce the risk of bursting. This goes from the rear of the jet ski directly to the supercharger barb on the Ultra 300. This will not fit the 310! The 310 utilizes 3 hoses instead of this. If you want to upgrade your cooling system we have a conversion kit and upgrade kit to upgrade the 300 cooling flow.