Kawasaki KAF820 Mule PRO-FXT Brake Bulb Size

Additional Notes

• The P21/5W is the brake bulb type specified for the Kawasaki KAF820 Mule PRO-FXT across all listed model years from 2015 to 2022.
• The P21/5W is a dual-filament bulb, meaning it contains two separate filaments within a single glass envelope. The higher-wattage filament (21W) serves the brake or turn signal function, while the lower-wattage filament (5W) serves a secondary running light function.
• The bulb operates on a 12V electrical system, which is standard for automotive and utility vehicle lighting circuits.
• The P21/5W uses a BAY15d bayonet base. The BAY15d designation indicates an offset dual-contact base, where the two pins are positioned at different heights to prevent incorrect insertion and ensure the correct filament is assigned to the correct circuit.
• The P21/5W is governed by ECE (Economic Commission for Europe) standards, reflecting its use in European and international vehicle lighting regulations rather than SAE standards used in North American markets.
• Because the BAY15d base is offset, it is not interchangeable with the BA15d base, which shares a similar bayonet form but has pins at equal heights. Substituting a BA15d bulb in a BAY15d socket would result in incorrect filament-to-circuit alignment.