These are not "spotless".
Even with high density RGB LED strips, the individual LEDs can still be seen through the milky white diffuser.
5X 1M Ultra-Thin Bendable LED Strip Installation Aluminum Channel System With Cover, End Caps & Mounting Clips - 1905-UTB
8 Review
2PACK Stainless Mesh Screen 12βX24β(305MmX610Mm), 20 Mesh 304 Steel Woven Wire Mesh, 1Mm Hole Sturdy Easy To Cut Never Rust By Valchoose
22 Review
MAPORCH 2 Pack 304 Stainless Steel Mesh Screen Woven Metal Type 5 Wire 29Cm X 60Cm (23.6β X 11.4β) For Vent, Animal Cage Net, Security, Cabinets
8 Review
Muzata 6-Pack LED Aluminum Channel System With Milky White Cover - 3.3Ft/1M Long And 17X14Mm U Shape - Spotless And Curved With 60Β° Angle - Perfectly Designed For LED Strip Lights
4 Review