This unique tool has been designed to allow for easy valve adjustment on most Toyotas overhead camshaft engines using spacer shims for valve adjustment. In operation, the tip of the pliers pushes between the spacer shim and the camshaft as the pliers are squeezed close. This action then moves the shim and its valve lifter down away from the camshaft lobe. In this down position the separate wedge tool is placed between the valve lifter ledge and the camshaft. This wedge tool then maintains a gap between the shim and the camshaft as the pliers are removed. The spacer shim can then be removed through this gap and replaced with one of the correct thickness. Made from quality heat treated alloy steel, this tool come as a set with pliers and spacer wedge. The 4605 does not work with Land Cruiser 1993-1997 and Lexus LX450 1996-1997.