Genuine OEM Volkswagen Brake Fluid Reservoir Cap, part number 1K2611349C. This cap is a critical component for the brake system, designed to securely seal the brake fluid reservoir. Its primary function is to prevent moisture and contaminants from entering the brake fluid, which could compromise braking performance. Made from durable plastic and weighing approximately 0.032 kg, it ensures a tight seal. Choosing a genuine OEM cap guarantees proper fitment, chemical resistance to brake fluid, and maintains the integrity of the hydraulic braking system, crucial for safety.