What's fair is fair. You just input the number of slices of cake you want to cut and LED lights around this equity-oriented cake tray illuminates the exact spots where you should cut, so each piece is evenly cut and nobody but nobody gets a bigger piece than anyone else. The tray will even play "Happy Birthday" (with volume control!) to the guest of honor. So let the party begin - with equality for all. Requires 2 AA batteries, not included. Measures 15 1/4" x 1 1/2" x 21 1/4". Spot clean only. One-year warranty.