Bautopart New Universal Adjustable Billet Aluminum Type Fv Turbo Blow Off Valve Bov Red The unique floating valve design incorporates a revised adjustable dual spring system and diaphragm ventilation The "FV" stand for Floating Valve, and it is this breakthrough in design that produces quicker valve response Another improvement includes an adjustable, sliding top hat, to adjust the hose fitting location, without complete dis-assembly FV also keeps its overall mounting and outlet dimensions Dual stage pull-type relief valve, will not leak under any lever of boost