Brass 1/2" Threaded Backplate [3048 PLU73569]
This Brass 1/2" Backplate is ideal for fixing a lampholder that has a 1/2" screw fixing in the base. The Brass 1/2" Backplate have 3 screw holes to fix to the wood (fixing screws not included).
The backplate is 25mm in diameter.
Screw fixing for these take 3x16mm countersunk for wood but other types of fixings would be needed for other matereials.