The Chrome Time and Tide Clock by Weems and Plath offers the following features:

Dimensions:  
Dial: 4 7/8” (125 mm)
Base: 6” (152 mm)
Depth: 1 5/8” (41 mm

Combination quartz and tide clock movement which averages the Atlantic 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.)
 

    *      Maintenance-free, ultra-hard finish guaranteed to NEVER tarnish
    *      Patented Slide-n-Lock™ Mounting System, no visible scrcews, easy mounting , easyremoval for adjustments & battery replacement
    *      Weatherproof construction for outdoor use
    *      Chrome finish
    *      Beveled glass crystal
    *      Includes AA Battery
    *      United States Patent #7,293,456
    *      Lifetime warranty on finish and movement

Product SKU: WP- 540300