Bosch common rail (CR) the man – volvo adjustment shim is an important adjustment component in diesel injectors that operates precisely under high pressure and contributes to maintaining stable injection pressure. It plays a role in the precise control of the amount of fuel injected by the injector. It is a standard component in almost all Bosch diesel injectors. To ensure high surface quality, superior wear resistance, and high measurement precision, it is manufactured with high accuracy using a lapping process.