It's fairly inexpensive and easy to create high power LED underwater lights. Like most everything to do with an ROV it comes down to the pressure vessel. These PVs were made from machined PVC with acrylic end cap. The wires are sealed using standard 150PSI screw down wire seals. These dimmable lights were made using the CREE 3-UP LED that is attached to a large aluminum heat sink with thermal epoxy. They are controlled through an Arduino.