[Material]: Chromium-vanadium steel, heat-treated. High hardness, wear-resistant and pressure-resistant. [Clamping mechanism]: Internal cam mechanism or knurled roller design. Automatically locks when torque is applied, ensuring a secure grip, preventing slippage and tooth skipping, and reducing thread damage. [Operation]: For use with a 1/2-inch ratchet wrench or a bent-handle ratchet. Rotate to engage the cam with the stud; continue rotating to complete removal or installation. [Dual-purpose]: Some models are suitable for both removal and installation. [Precautions]: Before use, ensure the stud diameter falls within the tool’s applicable range. When operating, ensure the clamping mechanism is fully engaged before applying force. Please confirm the required size before purchase., Manufacturer: AURVIX