Tool to make lining up #1 TDC for ease of installing the Distributor or to assist in valve adjustment. Simply tap into existing valve cover front bolt holes, and rotate engine camshaft sprocket to where its ball mark meets the "peg", to identify the location of #1TDC. This is necessary for the correct setting of a distributor, or the correct starting point for adjustment of your valve lifters. Much easier than trying to view the timing marks on the RH rear of the block to obtain the location of the flywheel "ball marker." The ball marker can also be aligned at #4 or #1 TDC. This tool ensures that you are at #1 TDC! Fits all Opel 1.5, 1.9, 2.0, 2.2 and 2.4L CIH engines. A must for your Opel tool collection!