Well, white rotating beacon then will do...![]()
Any colour light is OK to be on a vehicle if it is covered up or not connected up (excluding blue).
Only emergency vehicles can be fitted with a blue flashing light, or anything that looks like a blue flashing light, whether working or not.
click on reds link an see but read whole thing as the important bits are at the bottom of the pagehaha... well, mine is actually a go-anywhere camper van... but it's a secret so don't tell anyone
So... can I have blue, not connected, but not covered lights while on the road or not?