Impact Universal Joint, Black Oxide, Locking Yes, Overall Length 2 19/32 in/ OVERALL LENGTH: 2.500 INCHES NOMINAL OUTSIDE DIAMETER: 1.188 INCHES NOMINAL DRIVE SURFACE SIZE: 0.500 INCHES NOMINAL BOTH ENDS FEATURES PROVIDED: POWER TOOL DRIVE END SHAPE: SQUARE FIRST END EXTERNAL DRIVE END SHAPE: SQUARE SECOND END INTERNAL SPECIAL FEATURES: LOCK BUTTON (MALE END), LOCK BUTTON HOLE (FEMALE END) MATERIAL: STEEL OVERALL SURFACE TREATMENT: OXIDE OVERALL STYLE DESIGNATOR: 208 EXTERNAL-INTERNAL SPECIFICATION/STANDARD DATA: 05047-ASME B107.2 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD NONDEFINITIVE SPEC/STD DATA: 6 TYPE