Expansion Anchor Anchor Diameter 1/4 in Overall Length 1 3/8 in Screw Size 1/4 in Thread Size 1/4 In.-20 Thread Depth 0.5 in Thread Type Coarse Material Zamac Alloy Finish Plain Drill Bit Size 1/2 in Minimum Installation Depth 1 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 1 1/4 in