Fits '04-later XL, XR and '05-later Twin Cam-equipped models. Does not fit Screamin' Eagle Performance Heads with 5/16" diameter valves. This performance Beehive-shaped Valve Spring Kit will permit the Sportster engine to rev to 7000 RPM. The unique ovate wire yields increased performance from a compact spring design. The installed spring pressure is increased to 208 lbs, and allows a maximum lift of .575". Complete kit includes springs, upper collars and keepers, and lower collars with integral valve seals.