Bulbs P21/4W

4 products

P21/4W car bulbs – choosing the correct light source

The P21/4W is a dual-filament bulb with two power levels used in certain combined-function lamps. Its designation identifies a bulb type, but compatibility also depends on the requirements of the lamp and vehicle manufacturers.

How to select a P21/4W bulb

Check the marking on the original bulb or in the vehicle manual. Compare the base, contact arrangement, rated voltage, power and intended lamp function as applicable. Similar appearance alone does not confirm interchangeability. Check the exact contents of any multi-bulb pack.

Replacement and safe operation

Switch off the lights and let the bulb cool before removal. Install it in the correct position and use only a light source approved for the fitting. Avoid touching the glass with bare fingers where the manufacturer advises against it. Check the lights and their alignment after installation if required.

See other car bulbs and follow your vehicle's specifications.