Long countdown time setting: 999, 23 hours, 59 minutes and 59 seconds. Upgraded version: larger size. LCD screen size: 13.8cmx4cm/5.4x1.6in. It will alarm for sixty seconds when it reaches your set number. With clock function. You can switch between 12 and 24 hours. Easy to set. Two ways to place it. With magnetic back and movable bracket. Wide application: vacation, wedding, new baby, retirement, meeting, study and so on. How to set the clock: Press and hold the CLOCK button, see the clock number hour start flashing. Press UP/START or DOWN to adjust the specific number. Keep pressing CLOCK to set minutes - seconds. Press CLOCK again to start. In CLOCK mode, press the DOWN button to switch between 12 and 24 hours. How to set the countdown time: Press and hold the SET button, see a number start to flash. Press the SET button to get to the number you want to change. Press UP/START or DOWN to adjust the specific number. /START or DOWN, the number will change rapidly. Keep pressing SET until the screen stops flashing. Press the UP/START button to start or pause the countdown. Press and hold the UP/START and DOWN buttons at the same time to reset to 0. Requires: Internal 2 x CR2032 batteries (included) Color: Black Material: ABS Size: Approx. 15.5x5.7x1.1cm Package Contents: 1 * Digital Timer Clock The above package content only, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3 cm.