"Matter over Thread" LED Stip Illuminated Shower Niche Materials: Roma XL Easy-On IP65 Waterproof LED Channel, Opal LED diffuser for Easy-On XL Profiles, Endcap for RomaXL, 4 fl oz can of Starbrite Liquid Electrical Tape, and a 5M Nanoleaf Essentials Matter over Thread LED light strip kit. We planned a dimensioned gap between adjacent tile concrete backer board pieces that we were installing in the top of the niche, with one end of the gap opening into the adjacent wall. Installed Roma XL IP65 Waterproof channel into that gap along the entire length of only the top of the niche. Created routing path inside wall from the channel to the nearest cabinet interior (storage cabinet over the toilet with interior 120VAC outlet). Routed LED strip from the niche channel to the interior of the storage cabinet. Connected LED strip to power supply inside the storage cabinet. Connected Opal XL diffuser into the channel. See photos. Disclaimer: at the time of material purchase, Nanoleaf was the only "Matter over Thread" smart LED strip on the market, and it was not offered in a waterproof version, so extra care was taken to seal areas where steam could potentially penetrate.