This takes three AAA batteries which are not included. The light hooks over the rim of the toilet and shines into the toilet. There is a motion activated sensor that turns on the light so that it isn't staying on all night long. The sensor is to be aimed at the door so that the motion of someone walking in turns it on. My cats were setting it off and freaking themselves out while I tested it. I wanted to get this as a novelty gift for a white elephant party. 4 stars
"I received this product for free in exchange for an honest and unbiased review."