Thanks for the info on Lexel and the dual driver for MF03! That’s awesome. I also have a feeling those ring switches are wired to multiple pins.

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Some e-switches are just press fit, so no threads, just pressed into a hole. But personally no problem if threads need tapped, I have many metric taps and dies. Why would it require machining? It’s just a round hole, can be done with a drill bit.

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The reflector in the 1st light in the OP is aluminum.

I know they are machined for single led lights, but I assumed the aluminum ones in multi-emitter budget lights were die-cast then metal film coated on the reflective surface the same as machined ones are. But I don’t personally have any of those so I’m just guessing.

I’ve been advised that plastic reflectors can melt from the heat of a well driven emitter. Guess it depends on the plastic they use.