Features: 1. Application – Fits Benz M276 engine. 2. Replacement – Alternative to 6637 or 276589003300. 3. Function – This tool is specially designed to install the inner chain check valve at ease. Press the check valve into the hole flush and screw it into the cylinder head surface, and then turn the pressure screw until the plate is flush with cylinder head surface. 4. Material – Made of top high quality and wear resistance steel, durable and strong enough. .