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 switchable 12-hour and 24-hour formats. Easy to set and operate. Two placement options: magnetic back and adjustable stand. Suitable for various occasions such as vacations, weddings, baby care, retirement, meetings, study sessions, and more. How to set the clock: Hold the CLOCK button until the hour digits flash. Use UP/START or DOWN 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 SET repeatedly to cycle through the time units (days, hours, minutes, seconds). Use UP/START or DOWN to adjust the flashing number. Hold the button to change quickly. Continue pressing SET until the display stops flashing to save settings. Press UP/START to begin or pause the countdown. To reset, press and hold both UP/START and DOWN buttons simultaneously. Powered by 2 x CR2032 batteries (included). Color: white Material: ABS Dimensions: approximately 15.5 x 5.7 x 1.1 cm Package includes: 1 x Digital timer clock