Concrete Anchor Screw, Anchor Diameter 1/4 in, Overall Length 1 1/4 in, Head Type Hex, Head Width 0.31 in, Head Diameter Not Applicable, Drive Type External Hex, Material Steel, Material Grade/Class Low, 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 1/4 in, Maximum Ultimate Shear Strength 1,440 lb, Maximum Ultimate Tension Strength 950 lb