The Nite Ize NiteGem is a small gem-shaped LED light for adding a splash of colour around the house, garden, campsite or poolside. It uses Disc-O Select technology: choose one of six fixed colours, or set it to colour-changing Disc-O mode, which cycles smoothly through the colours. The NiteGem is waterproof and floats, so you can drop a few into a pool, bath, hot tub or cooler box, set them on a table as party lights, or put one in a tent as a soft night light. It runs on two replaceable CR2016 batteries, which are included, and gives about 20 hours of light per set. The frosted, rounded shell spreads the light evenly.