THIS IS A COMMAND BT30 TOOL HOLDER, PART NUMBER B2U4-0003, FEATURING A CAT30 TAPER TYPE. THE OVERALL LENGTH (OAL) IS 5 INCHES, WITH A PROJECTION OF 2.08 INCHES. THE BODY OUTSIDE DIAMETER (BODY OD) MEASURES 1.25 INCHES, AND THE BORE INSIDE DIAMETER (BORE ID) IS 0.75 INCHES.