Long setting countdown time: 999 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 inches). Sounds an alarm for sixty seconds when the set time is reached. Includes clock function with 12-hour and 24-hour format options. Easy to set. Two placement options: magnetic back and adjustable stand. Wide application for vacation, wedding, new baby, retirement, meetings, study, and more. To set the clock: Press and hold the CLOCK button until the hour flashes. Use UP or DOWN to adjust. Press CLOCK repeatedly to set minutes and seconds. Press CLOCK again to confirm. In clock mode, press DOWN to switch between 12-hour and 24-hour formats. To set countdown time: Press and hold the SET button until a number flashes. Use UP or DOWN to adjust the desired value. Continue pressing SET to cycle through settings until flashing stops. Press UP to start or pause countdown. Press and hold UP and DOWN together to reset to zero. Powered by 2 x CR2032 batteries (included). Color: Black. Material: ABS. Size: Approximately 15.5 x 5.7 x 1.1 cm. Package includes: 1 x Digital timer clock. Only the above content is included; other items are not. Note: Lighting and display differences may cause slight color variations. Measurement allowance is +/- 1-3 cm.