Expansion Screw Anchor Anchor Diameter 5/16 in Overall Length 1/2 in Screw Size #8 Thread Size #8-32 Thread Depth 0.4063 in Thread Type Coarse Material Zamac Alloy Finish Plain Drill Bit Size 5/16 in Minimum Installation Depth 1/2 in System of Measurement Inch Expansion Anchor Type Caulking Anchor Material Grade/Class Not Graded Compatible Material Block Brick Concrete Stone Installation Method Machine Screw Minimum Hole Depth 1/2 in Manufacturer Location Made in USA