Camshaft adjusting socket set or timing tools kit designed for specific Volkswagen (VW) and Audi vehicles. This specialized tool kit is used for: The removal and installation of the 4/3-way central control valve for camshaft adjustment. Rotating and holding the intake camshaft in place during timing chain service. The tools are compatible with various VAG engines, including: 1.8L and 2.0L (4v) generation 1, 2, and 3 TFSI chain-driven engines. Specific models like the Audi A3, A4, Q5, TT, and Volkswagen GTI, Jetta, Passat. The set includes different sized sockets with unique 2-pin positions and typically features a 3/8" square drive.