The Limelight single color NoDot LED's have a unique double core designed to help protect the stripsfrom the elements. However when the strips are cut to length for installation, the end becomes open to the elements. To help seal the ends of the LED strips we custom make these silicone caps that can be glued onto the end of the strips to maintain a waterproof strip. Installation is easy, just a little dab of silicone sealant inside the cap is all that is needed. We suggest the use of Sil-Poxy to glue them in place, as it creates a super strong connection not easily removed and is available on Amazon.