399 Hour Timer
Set the timer for the specified time
Countdown
Set timer for 399 Hours. Wake me up in 399 Hours. Set the alarm for 399 Hours from now. It is a free and easy-to-use countdown timer.
Set the hour, minute, and second for the online countdown timer, and start it. Alternatively, you can set the date and time to count till (or from) the event.
Start 399 Hour timer.