This light can be synced as an accessory to all our VS wireless bite alarm sets. The central LED colour can be matched to those on your alarm and receiver so that you know which rod is going off. At the same time, the surrounding LEDs will light up in white providing instant light at night. It can also be used as a standalone bivvy light. Its easy to attach to your bivvy using the magnets and backing plate included and has 4 brightness settings. Its also USB rechargable. so no need to worry about batteries!