Usage: Press The S Button To Set The Second Display Position, Press The M Button To Set The Minute Display Position, Press The Start / Stop Button To Start Or Stop, And At The Same Time Press The Ms- Button To Reset The Display To Zero. An Alarm Occurs When The Set Time Counts Down To Zero SecondsFunction: Countdown Function, Can Count Down Up To 99 Minutes 59 Seconds, Automatically Return To The Set Countdown Time When The Countdown Is Complete; Counting Function, Press The M And S Buttons At The Same Time To Reset, Then Press The Start Button To Start Counting.Product Attributes: Outside Size: 7.5 * 6.8 Cm, Window Size (Lcd): 6.5 * 4 Cm With A Conventional Aaa Battery (This Product Does Not Have A Battery, You Need To Buy It By Yourself)Small And Portable: There Are Magnets And Brackets, Free Hanging Holes On The Back; It Can Be Attached To A Metal Surface, Placed On A Table, Or Hung; There Is A Foldable Hanging Hole Above The Clip That Is Suitable For Hanging On A NailLarge Screen: Large Numbers Are Clearly Displayed, Three-Button Design, Simple And Convenient Operation And Setting. The Back Of The Product Has A Rear Clip That Can Be Clipped Onto The Belt.