6061 Billet Aluminum Panel Pressure Relief Captured O-Ring Grove Why Our Plate?:Our Billet Bolt-On Pressure Relief panels are second to none in both quality and performance. Features:6061 Billet aluminum plate, Spring loaded panels, Sealed with a captured grove o-ring, Studs are pressed in. The relief plates can help save your intake in the event of a cough or backfire! The spring loaded panel will unseat allowing the pressure to escape instead of destroying your intake. Cheap insurance! Application:Fits any flat or machined area on the plenum that accepts 3 5/8 x 2 1/4 with bolt holes 3" center to center. *Note What sets our Relief panel apart from the others, The captured grove for the o-ring allows the o-ring to style seated in the event of the panel opening unlike others blowing out!