Is this waterproof?

[mattylad]

Just flick the breakers off as you walk past ....

 

[SimonH2]

It is often better to simply ensure gap in seal or drilled hole at bottom so any water can exist. What can happen is where the unit is heated and cooled, water can be sucked in as it cools, if there is a gap at bottom next time it heats up it is forced out again, but anywhere else it slowly builds up over time.

Yes, the lamps that recovered got holes drilled in them, no more have filled up since. Need to get some more to replace the ones that were terminal - they'll get holes in them from the outset.