Dave Liquorice wrote:
I've got light fitting that has the cover retained by some tamper proof
screws. The heads have a raised equilateral triangle with each side 4 or
5mm long. This obviously needs a triangle shaped socket driver, can I
find one? Can I heck. That's looking on CPC and RS sites. The "security"
bit sets don't have this particular type of bit in them.

It occurs to me that the appropriate sized hex socket bit may work.