EngValve Spring Seat, Locators 1.30" OD .510" .060 Thick, ID Spring Locator Set of 16 - 1.300" OD, .510" ID, .060" Thickness, None, Made from hardened steel, these locators use an inboard locating shoulder to center the seat and hold the spring in place. The 4861 features a 1.300" OD and a .510" ID., Engine Valve Spring Seat.