They fit perfectly into the Quartz by ACO grills (all six - excluding the tile top version) and are activated by running water. In my field testing I found that it is far easier to cut out the factory spacers from the grill with metal snips and use the new spacers that come with the lights.
The new spacers and installation of the lights took me under 5 minutes for the first round and after this future re and re's where about 2 minutes.
The instructions for these lights come in German and to my knowledge there is still no English version. If you need a translated copy a great client of mine did this for me.
Take a look at yesterdays install;
The Soundtrack is from my new favourite Reggie Band "Katcha Fire". Click here to buy their album