Self Locking Thread Insert Compatible Material Concrete Compatible Tap Size Not Applicable Drill Bit Size 3/8 in External Thread Fit Not Applicable External Thread Size Not Applicable Finish Zinc Plated Insert Diameter 3/8 in Internal Thread Fit 2B Internal Thread Size 1/4 In.-20 Material Steel Material Grade/Class Grade B7 Maximum Hole Diameter 0.375 in Minimum Installation Depth 1 5/8 in Overall Length 11/16 in System of Measurement Inch Thread Direction Right Hand