Overall Length4.16Wrench Size3-3/4Opening ShapeRoundedWrench End TypeOpen EndWrench Body TypeStraightWrench VariationStandardDrive TypeInternal SquareDrive Size3/8Center-to-Center Distance2.86Head Thickness1.00Fastener NumberB183S40Where Used112W1003 (rear spar assembly)Used WithST2580-545-2