These silicone end caps are used for re-sealing any IP65 rated, waterproof RGB LED strips such as NeoPixels, WS2812B, SK6812. They're particularly useful in case you want to cut them to a custom length. The translucent silicone material perfectly it's similar to the sleeve of the strip, which helps maintain the inconspicuous look, and doesn't occlude the light emitted by the LEDs.
Each end cap is 12mm wide and includes 4-holes, so they fit most 3- and 4-pin LED strips out there!
For your convenience, both end caps include the 4 holes that allow you to easily route cables. The cables are used to connect the enclosed, flexible PCB to a power source, controller, and/or other strips. If a connection isn't needed on one end of the LED strip, the holes are small enough that they're easy to 'plug' with the same silicon glue you use to hold it in place.
