Combination quartz and tide clock movement which averages the lunar tide cycle. The tide sector is calibrated for the east coast of the United States. Uses a AA battery. (Note: The clock will work for other tidal bodies of water but will need to be re-set more frequently.) Dial: 3-3/4". Base: 5-1/2". Depth: 2-7/8". Wt. 11 oz.