This Fish Strike Alert is the ideal indicator for night fishing， it can effectively solve these difficulties that whether the fishes rise to the bait at night. It is used of the temptation effect of green light on fishes， light flashes green slowly when steady and light flashes red quickly with fish strike，very obviouslyGreen-Ready; Red- Fish OnVisible from 100 yards Fits onto a majority of rods Automatically activated when fitted to the rod tip sectionWater resistant， so can be used in rainBattery life up to 1000 hours Features:Power: CR1225 button cell battery(included)Diameter: 18mmWeight: 4g