Concrete Anchor Screw Anchor Diameter 1/4 in Overall Length 3 1/4 in Head Type Hex Head Width 0.31 in Head Diameter Not Applicable Drive Type External Hex Material Stainless Steel Finish Silver Climashield Material Grade/Class 410 Removable Removable Compatible Material Block Brick Concrete Drill Bit Size 3/16 in Screw Anchor Type Concrete Screw Anchor System of Measurement Inch Maximum Material Thickness 2 1/4 in Maximum Ultimate Shear Strength 1 440 lb