Long setting countdown time: 999 days, 23 hours, 59 minutes and 59 seconds. Upgraded version with larger size. LCD screen size: 13.8 cm x 4 cm / 5.4 x 1.6 in. Alarm sounds for sixty seconds when the set time is reached. Includes clock function with 12-hour and 24-hour format options. Easy to set and operate. Two placement options: magnetic back and adjustable stand. Suitable for various occasions such as vacations, weddings, baby arrivals, retirement, meetings, and studying. How to set the clock: Hold the CLOCK button until the hour starts flashing. Use the UP/START or DOWN button to adjust the hour. Press CLOCK again to set minutes and seconds. Press CLOCK once more to confirm and start. In clock mode, press the DOWN button to switch between 12-hour and 24-hour formats. How to set countdown time: Hold the SET button until a number starts flashing. Press the SET button to navigate to the digit you wish to change. Use the UP/START or DOWN button to adjust the selected number. Continue pressing SET until the display stops flashing. Press the UP/START button to begin or pause the countdown. To reset to zero, press and hold both the UP/START and DOWN buttons simultaneously. Requires 2 x CR2032 batteries (included). Color: black Material: ABS Size: approximately 15.5 x 5.7 x 1.1 cm Package Contents: 1 x Digital timer clock Note: Light and screen display differences may cause slight color variations between the image and the actual item. Measurement may vary by +/- 1-3 cm.