Key Locking Thread Insert System of Measurement Inch Insert Diameter 5/16 in Overall Length 5/16 in Internal Thread Size #8-32 Internal Thread Fit 3B External Thread Size 5/16 In.-18 External Thread Fit 2A Thread Direction Right Hand Thread Type Coarse Material Steel Finish Black Phosphate Wall Type Heavy Wall Number of Locking Keys 4 Compatible Material Metal Compatible Tap Size 5/16 In.-18 Drill Bit Size I Minimum Installation Depth 3/8 in Maximum Hole Diameter 0.272 in