Long setting countdown time: 999 days, 23 hours, 59 minutes and 59 seconds. Upgraded version: bigger size. LCD screen size: 13.8cm x 4cm / 5.4 x 1.6in. It will alarm for sixty seconds when reaching the set time. With clock function. Switch between 12 and 24-hour format. Easy to set. Two placement options: magnetic back and adjustable bracket. Wide application: vacation, wedding, new baby, retirement, meeting, study, and more. How to set the clock: Hold the CLOCK button until the hour starts flashing. Press UP/START or DOWN to adjust the hour. Press CLOCK to move to minutes and seconds. Press CLOCK again to confirm and start. In clock mode, press DOWN to switch between 12 and 24-hour format. How to set countdown time: Hold the SET button until a number starts flashing. Press SET to move to the digit you want to change. Press UP/START or DOWN to adjust the value. Continue pressing SET until the display stops flashing. Press UP/START to begin or pause the countdown. Press and hold UP/START and DOWN together to reset to zero. Requires: 2 x CR2032 batteries (included) Color: black Material: ABS Size: approximately 15.5 x 5.7 x 1.1cm Package Contents: 1 x Digital timer clock Only the above items are included; other items are not part of the package. Note: Lighting and display differences may cause slight color variation between the image and the actual item. Measurement may vary by +/- 1-3cm.