If you have never played frisbee at night you are really missing out this led glow frisbee runs for 30 hours on 1 set of batteries is competition size amp weight floats very durable and is the best glow frisbee we have seen at this pricer r each frisbee runs on 2 cr2016 batteries which are widely available and cheap to replace but you wont be doing that much as the set included will last up to a staggering 30 hours of constant user r an absolutely fantastic product that will give you l