Universal Joint Adaptors, 1/2" (female square); 1/2" (male square) drive, 2 1/2"

Designed for superior performance with steel pin and tension washer construction for added strength, no binding or locked joint. Forged and machined for best fit and unyielding strength. Precision Heat-Treated and tempered for optimal hardness, ductility and durability. Easy to read stamp pattern in order to quickly determine opening size. Meets and exceeds ASME B107 hand tool standards.