Replacement bulbs for trailer lamps in 12 V, singly and in tens.
On a bulb lamp the bulb is replaced on its own, without changing the lamp.
How to choose a bulb
The base code decides the fit. BA15S has one contact and a plain bayonet base, BAY15D has two contacts and offset pins so it can only go in one way round, and SV8.5 is a festoon bulb that sits between two spring contacts. Read the code off the old bulb.
Wattage
The wattage has to match what the lamp is built for. A 21/5 W twin filament bulb carries both the brake and the tail function in one base. The code on the old bulb settles it.
Replacement bulbs
For lamps without bulbs see LED rear lights. For lorry bulbs at 24 V see bulbs for lorries.
