RGB Swith that will be used in a new Keyboard from Steelseries:
Steelseries Apex M80
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Vortex did PBT+POM double-shot keycaps for backlighting, nominated in the 2014 DTA.
Indeed, but I mentioned them because people often assume that half-translucent doubleshot PBT couldn't be made.
You could use an adapter for MX stems, but it would be like with Alps and Commodore 64 adapters: the caps would be higher even if the obstructing LED would be removed. Because the square Kailh stem is off centre by 1.5 mm, the Cherry MX keycap stem cylinder would have to be max 4.2 mm instead of 5.5 wide - if there wasn't any LED in the way.