The OPTIMAL Deflection Pulley Guide Pulley Timing Belt (0-N866) is a professional-grade replacement component engineered for long service life and reliable operation across all conditions your vehicle encounters. The part is built to the following specification: Width [mm]: 21 mm, Outer Diameter [mm]: 50 mm. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Verified to fit BMW models. All compatibility data is cross-checked against the TecDoc database — select your vehicle to confirm the part matches your specific engine and year. This part supersedes original equipment references: 02560, 08.12.009, 11 13 1 721 264, 11 13 1 727 141 and 33 more. Matching these numbers confirms a like-for-like replacement with no loss of function. OPTIMAL is a recognised supplier of automotive engine timing components to independent workshops and dealer networks across Europe. All parts are sourced from authorised distribution channels and carry full manufacturer traceability — you receive exactly the same component supplied to professional garages and dealer workshops. If fitment or specifications do not match your vehicle, our technical team can help identify the correct alternative — use the vehicle selector or contact us with your VIN for a guaranteed-fit recommendation. Replacing worn components on schedule preserves your vehicle's safety, reliability, and resale value — and aftermarket parts from established brands deliver OEM-equivalent performance at a fraction of the dealer price. Every part is dispatched from our UK warehouse with a 30-day money-back guarantee and free hassle-free returns.

OPTIMAL, founded in Germany, is a well-regarded aftermarket brand specialising in steering, suspension, and wheel bearing components. OPTIMAL produces ball joints, tie rod ends, control arm bushings, wheel bearings, and stabiliser links for European, Asian, and American vehicle applications. Manufactured to stringent quality standards with comprehensive testing protocols, OPTIMAL parts deliver OE-matching fit and performance. Known for excellent value and wide vehicle coverage, OPTIMAL is a popular choice among professional workshops across Europe.