In my early days of motoring you had to have a parking light, they were not the cheapest thing to buy, and of course you need a cigarette lighter to plug them into which was not always standard, of course if you were a car meddler, you could wire it to the car electrics and have a inline switch. 16/6p (83p) was a lot of money back then, yet today it cost me twice as much for a cream bun