Flex Socket, 1/4" Dr, 7/16", 12 Pt./ OVERALL LENGTH: 1.156 INCHES NOMINAL WRENCHING SURFACE SIZE: 0.438 INCHES NOMINAL SINGLE END DRIVE SURFACE SIZE: 0.250 INCHES NOMINAL SINGLE END FEATURES PROVIDED: MANUAL TOOL WRENCHING SURFACE SHAPE: 12 POINT SINGLE END INTERNAL DRIVE END SHAPE: SQUARE SINGLE END INTERNAL MATERIAL: STEEL OVERALL SURFACE TREATMENT: CHROMIUM OVERALL STYLE DESIGNATOR: 169 UNIVERSAL JOINT