Expansion Anchor Anchor Diameter 1/2 in Overall Length 2 1/2 in Screw Size 1/2 in Thread Size 1/2 In.-13 Thread Depth 0.75 in Thread Type Coarse Material Zamac Alloy Finish Plain Drill Bit Size 7/8 in Minimum Installation Depth 2 1/4 in System of Measurement Inch Expansion Anchor Type Double Expansion Anchor Material Grade/Class Not Graded Compatible Material Block Brick Concrete Stone Installation Method Machine Screw Minimum Hole Depth 2 1/4 in