Flora NeoPixel 60 RGB LED Strip in 4M Reel - Black Backing
These NeoPixel strips have 60 digitally-addressable pixel LEDs per meter and are very affordable and are only 12.5 mm wide, 10 mm if you remove the strip from the casing. This strip is the strip with Black flex PCB, its identical to the White 60 LED/meter except it has a different color mask on the flex strip.