This Graco Drill Fixture Combo works for two models, the 575S and the 575A. This fixture has four mounting screw holes, two holes marked "S". Once the screw holes have been drilled into the stock for mounting the butt plate, the same holes can be used to hold the fixture, as well as provide the correct position for drilling. Unit comes complete with steel plate, 1 1/8" multi-spur bit and drill bushing. FeaturesEnhanced Precision: Achieve exact drilling for accessory installations, leading to improved firearm performance and aesthetics.Time Efficiency: Streamline the customization process with tools designed to simplify complex drilling tasks.Professional Results: Obtain a high-quality finish in your gunsmithing projects, reflecting the standards expected by professionals.