I have some hardware that has screwholes but I want to mount it to the wall such that it can be easily removed. Is there some kind of adapter I can purchase such that it can be unclipped easily in the same manner as hardware that has 'keyhole' slots?
If the battery holder has enough room in the holes where the screws go, that you could drill another hole below it, but larger, that the screw head can pass through, then slide down, then yes. I bought one like that just about 2 weeks ago, and the holes were beneath the AA battery slots and centered in the slot. No way to extend the hole to make it moveable. But, you could mount it to a thin board or wooden paint stirrer, yardstick, wood ruler, etc. Then you can drill a small hole in the upper section, with a larger one below and cut a slot between them to slide the screw on to. I am not aware of any adapters, but easy to make your own.