Set the time and it counts down to completion. Easy to use. Counts down in seconds (up to 99 min. 59 sec.) or in minutes up to 9999 minutes. Can be used silently or with audible beep confirmation. Automatically resets to preset time at completion. Stop and restart for time-outs. Lock function protects the current setting which is entered. Break-away safety lanyard helps prevent accidents, promotes safe use. Choose blue, orange, red, green, yellow, purple. Comes ready to use with LR44 battery. One year warranty.