The new Edelbrock Spring Seat Locator Kit #5799 (set of 16) is intended for applications that require the use of hardened valve spring seat locators. This includes all of the complete Edelbrock cylinder heads that use the 1.54-inch Dual Valve Springs #5823 for solid roller lifter camshafts such as the Big-Block Chevy Performer RPM and the 460 Ford Performer RPM cylinder heads. These valve spring seat locators have a thickness of .060 inch and will provide a hardened barrier between the valve springs and the aluminum cylinder heads while positively locating the base of the valve spring.