With loud alarm ( minute, the beep sound differs per channel). It start to count up when of the countdown time is reached. So you know how long it has passed. It is useful when you are cooking. OCCASION -- cooking, classroom, laboratory, fitness, beauty, children eating, sports, meeting,etc. The maximum setting time is: 99 hours 59 minutes 59 seconds.Each timer has its own sound so you can tell which one is going off. Product Name: Digital Count Up Down Timer 3 Modes: clock + countdown timer + stopwatch 4 channel countdown timer.The 4 sets of give you some flexibility. It can be used at the same time when baking several different batches of something. It starts to count up at of your set countdown. to place the timer: Stand / Magnet / Hang. You can attach it on your fridge; Stand it up on your kitchen counter; or hang it . Large and clear digits display. Clock Mode: CLOCK button for about 2 seconds until the time starts to flash. " button to set "hour", "MIN" to set "minute", and "SEC" to set "second". CLOCK button to exit the setting screen. Countdown Timer Mode: a timer button (T1-T4) to select a timer. to set "hour", MIN to set "minute", and SEC to set "second". Holding down any button (/MIN/SEC) to increase its setting at high speed. START/STOP to start/pause the timer. Stopwatch Mode: When the timer setting is zero, START/STOP,timer start to count up. the START/STOP to start or pause Stopwatch. Timer Weight: 86.3g / 3.04oz Requires: 2 x AAA batteriesNot included colour:White, gray Material:plastic size:848435mm LCD Size: 54mm * 23mm (2.13*0.91 in) Package Contents: 1x Digital Countdown Timer Note: CLEAR to clear the timer setting to all zeros. The beeper continues for one minute or the START/STOP button. Each timer has its own sound. It start to count up when the setting