Long countdown setting: up to 999 days, 23 hours, 59 minutes, and 59 seconds. Upgraded version with larger size. LCD screen measures 13.8 cm x 4 cm (5.4 x 1.6 inches). Sounds an alarm for 60 seconds when the set time is reached. Includes clock function with 12/24-hour format toggle. Easy to set and operate. Two placement options: magnetic back and adjustable stand. Suitable for various uses such as vacations, weddings, baby tracking, retirement, meetings, and study sessions. To set the clock: Press and hold the CLOCK button until the hour digits flash. Use UP/START or DOWN to adjust the hour. Press CLOCK repeatedly to cycle through minutes and seconds. Press CLOCK again to confirm and start. In clock mode, use the DOWN button to switch between 12-hour and 24-hour formats. To set the countdown timer: Press and hold the SET button until a digit flashes. Use the SET button to navigate to the value you wish to adjust. Use UP/START or DOWN to change the value. Hold UP/START or DOWN for faster adjustment. Continue pressing SET until the display stops flashing. Press UP/START to begin or pause the countdown. To reset the timer to zero, press and hold both UP/START and DOWN buttons simultaneously. Powered by 2 x CR2032 batteries (included). Color: Black. Material: ABS. Dimensions: Approximately 15.5 x 5.7 x 1.1 cm. Package includes: 1 x Digital timer clock. No other items included. Note: Lighting and display differences may cause slight color variations between the product image and actual item. Measurement may vary by +/- 1-3 cm.