When alternator regulator performance matters, the HELLA 5DR 009 728-421 delivers — built to the same dimensional and material standards as the original part it replaces. The part is built to the following specification: Voltage [V]: Zinc V, Manufacturer Restriction: Bosch, Operating voltage [V]: Nylon, Rubber V, Alternator Number: 0 124 315 025, Alternator Number: 0 124 315 029. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Compatible with TOYOTA vehicles; use the vehicle selector above to confirm exact fitment for your make, model, and engine variant. Fitment data is sourced from TecDoc, the authoritative European parts catalogue. This part supersedes original equipment references: 009 728-421, 009728421, 0 124 315 016, 0 124 315 024 and 22 more. Matching these numbers confirms a like-for-like replacement with no loss of function. HELLA is a recognised supplier of automotive replacement 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.

HELLA, founded in 1899 in Lippstadt, Germany, is a global automotive lighting and electronics specialist now operating as FORVIA HELLA. HELLA specialises in headlamps, rear lights, signal lighting, sensors, actuators, and electronic control units. As an OE supplier to virtually all major car manufacturers, HELLA products represent the cutting edge of automotive lighting and electronic technology. With 125+ years of innovation in vehicle illumination and electronics, HELLA is the definitive choice for high-quality lighting and electronic component replacements.