This belt pulley is a new replacement part designed for the Volkswagen Transporter T4, as well as for its Transporter T4 Syncro version. It is part of the alternator drive circuit and plays an essential role in ensuring proper electrical charging of the vehicle. As part of the restoration or regular maintenance of a classic Transporter T4, its replacement helps prevent any risk of belt breakage and ensures the reliability of the entire accessory drive system.