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 in). Alarm sounds for sixty seconds when the set time is reached. Includes clock function with 12-hour and 24-hour format selection. Easy to set and operate. Two placement options: magnetic back and adjustable stand. Wide range of applications: vacation, wedding, new baby, retirement, meeting, study, and more. How to set the clock: Hold the CLOCK button until the hour digits start flashing. Press UP/START or DOWN to adjust the hour. Press CLOCK again to move to minutes, then seconds. Press CLOCK once more to confirm and start. In clock mode, press the DOWN button to switch between 12-hour and 24-hour format. How to set countdown time: Hold the SET button until a number starts flashing. Press SET to cycle through digits to be adjusted. Use UP/START or DOWN to change the selected number. Continue pressing SET until the display stops flashing. Press UP/START to begin or pause the countdown. To reset to zero, press and hold 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 (Only the above items included; other items not included) Note: Lighting and display differences may cause slight color variations between the image and the actual item. Measurement may vary by +/- 1-3 cm.