This tool is part of CTA 4380 spare tire tool kit. Use for removal & installation of spare tires mounted under vehicle. Tool length - 24"/ 61cm. Tool must be used with CTA 4351, 4352, 4353, 4354, 4355, 4356, 4359 or 4360. The square drive system between the hand crank and tool is 12mm. You cannot and should not use impact tools with this system. You should never use impact tools when removing or installing the spare tire. The crank provides sufficient torque and avoids damage to the tools and the spare tire hoist. Whether tuning up your '68 Corvette or changing the oil on a John Deere TRACTOR, CTA can supply you with the tools needed to do the job. California prop 65 - warning, this product contains chemicals known to the state of California to cause cancer, birth defects or other reproductive harm.