Versatile size range: This single tool effectively removes and installs studs in a wide range of sizes from 1/4 inch (6mm) up to 3/4 inch (19mm) (approx. M5 - M18), making it an essential, multi-purpose tool for automotive repair, machinery maintenance, and serious DIY projects. 1/2" drive for superior leverage: Built to work with a standard 1/2" drive ratchet or breaker bar, giving you the maximum torque needed to break free the most stubborn, frozen studs without damaging the threads or rounding the head. Grips tighter with torque: Features an ingenious internal cam mechanism. As you apply force with a 1/2" drive ratchet, the tool rotates and locks onto the stud's threads with increasing pressure, providing a secure, non-slip grip for the successful removal of seized or rusted studs. Professional stud removal tool: Specifically designed to remove intact but stubborn studs (like head studs, main studs, or carburettor studs) that are difficult to loosen with traditional methods Dual-purpose design: Use it for both removal and installation. The robust, heat-treated chrome vanadium steel construction ensures maximum durability and resistance to wear, providing a reliable, long-lasting solution for your workshop needs.