These NOS blowdown hose kits are available with 90 or 180 degree bottle fittings and straight or 90 degree exit fitting offering you many fitment choices. Also included is a 36 inch length of stainless steel braided Speed-Seal hose and a choice of black Speed-Flex fittings. This type of hose kit is necessary when mounting a nitrous bottle inside the passenger compartment or trunk of a vehicle. It directs the nitrous outside of the vehicle in the case of an over-pressurization event.