alanblaby:
I've seen them a few times, we just swap them for std. 2 pin bayonet pendants, as standard GU10 lamps will not fit in due to the deep base.
Another one we have is a 3 pin bayonet fitting. Only one block of flats I deal with has these.
https://www.bltdirect.com/6-inch-pendant-lamp-holder-for-22mm-bc-3-pin
Standard 2 pin bayonet lamps will not fit in the holders, even though at first it looks like they will - the pin locators are slighlty offset.
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