For Screamin\' Eagle heads. Installed pressure 217lbs@1.789\", open pressure & height 415lbs@1.215\", coil bind@1.125\". Direct replacement, installs without machining or rocker box clearancing. High tensile chrome silicone wire with a shot-peened heat treatment and a super NexTex® finish. Kits include springs, lower collars, titanium upper collars, shims, keys and Viton® seals.