Socket Adapter, Input Drive Size 3/8 in, Input Drive Shape Square, Input Drive Gender Female/ OVERALL LENGTH: 2.125 INCHES NOMINAL DRIVE SURFACE SIZE: 0.375 INCHES NOMINAL BOTH ENDS FEATURES PROVIDED: MANUAL TOOL DRIVE END SHAPE: SQUARE FIRST END INTERNAL DRIVE END SHAPE: SQUARE SECOND END EXTERNAL SPECIAL FEATURES: LOCKING TYPE; INCLUDES HEX KEY FOR SET SCREW MATERIAL: STEEL OVERALL SURFACE TREATMENT: OXIDE OVERALL STYLE DESIGNATOR: 69 RIGID SPECIFICATION/STANDARD DATA: 0U583-SAE AS4283 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD NONDEFINITIVE SPEC/STD DATA: 2 TYPE AND 2 CLASS