Key Locking Thread Insert System of Measurement Inch Insert Diameter 1 3/8 in Overall Length 1 3/8 in Internal Thread Size 1 In.-12 Internal Thread Fit 3B External Thread Size 1 3/8 In.-12 External Thread Fit 2A Thread Direction Right Hand Thread Type Fine Material Steel Finish Black Phosphate Wall Type Heavy Wall Number of Locking Keys 4 Compatible Material Metal Compatible Tap Size 1 3/8 In.-12 Drill Bit Size 1 5/16 in Minimum Installation Depth 1 9/16 in