You are looking at a pair of lovely British-made antique light switches. they are 5.5cm in diameter and in great vintage condition with no major defects. I have not tested them, but the mechanism appears to be in perfect working order.
I have given them a quick polish but if you want to return them to their original shiny brass condition, then simply give them a quick once over with very fine grade wire wool to get rid of the oxidation.
For the avoidance of doubt, the price is for one lightswitch, not the pair.