Micro 100 TH-208 Boring & Grooving Bar Holders; Inside Diameter (Inch): 3/8 ; Inside Diameter (Decimal Inch): 0.3750 ; Outside Diameter (Decimal Inch - 4 Decimals): 0.7500 ; Outside Diameter (Inch): 3/4 ; Overall Length (mm): 69.85 ; Overall Length (