The HKS SSQV and Racing Type II blow-off valves are sold in a universal application. These are adapter flanges that allow you to mount the HKS valves in a variety of applications, whether welding directly to intake/intercooler piping, or connecting via a hose. They are available in steel or aluminum to suit your installation needs. The sizing is for the approximate diameter pipe you will be welding the flange to.
Steel for 50mm pipingSteel for 65mm pipingAluminum for 60mm pipingHose Fitting for 30mm/1.25inch Hose
These are adapter fittings that attach into the front outlet snout of the HKS SSQV blow-off valves and allow you to run it closed-loop, recirculating the releaesd air back into the intake system.
Select the size based on the inside diameter of the hose you will be connecting it to.