300M /Middle Stop Light on trunk

In replacing this bulb, I only had one of the bulbs used in my outdoor
lighting (low V/) put it in and it works fine... any possible problems in
doing this? It is a trip to go to auto store and thought it looked the same
, and by golly it works... thanks to this super group for many problems
solved and a very Happy New Year.
Ralph Griffith

 

Some LV architectural lighting does indeed use 12v bulbs of the same
form factor as some automotive lights. But the wattage must be correct,
so check it carefully to make sure it matches, because there are about
eight differently-rated bulbs in that exact form factor. They'll all
fit and light up, but if you install one of too low a wattage, your
centre brake light won't be bright enough. If you install one of too
high a wattage, the centre brake light will be too bright until it
melts.