Use as hall passes for restroom breaks, errands and more--three passes in one convenient system. Allows teachers to easily and effectively manage the busy classroom. Track progress from the three timers on the base station. Timers encourage independence, accountability and a natural sense of elasped time as they count up or down. Each timer measures 3 1/2"H and features a light, an optional audio alarm, 30-second time warning, belt clip and wrist strap for maximum portability. Width: 10 1/2"; Depth: 4 1/2"; Height: 5".