General description The Laser Tools Injection Pump Locking Pin 3551 is designed for use with diesel injector high pressure pumps, effectively locking the fuel pump in its timed position. This essential tool is commonly included in various diesel VAG timing kits. Technical specifications Pin diameter: 6mm Compatibility and accessories Included in kits: 3472, 3574, 3978, 4346, 4772, 4684, 4867, 5130, 6557, and 7588