Water powered thermometer alarm clock. Keeps perfect time without requiring batteries or electricity. Just fill the reservoir with tap or rain water, and the clock will work for up to a few months. A fresh watering of the clock continues operation an internal memory chip retains the clock’s time (for 2 minutes) during a refill so resetting the time is not necessary. A button cycles between month/date and time on the LCD screen. Size: 11.7 x 7.3 x 5 cm.