Time and Tide Clocks are useful and exciting additions to any coastal home. They are perfect for swimmers, beachcombers, fishermen, surfers and boat owners, offering a simple and reliable way to tell the time of the local tides, along with time of day ---at a glance.The tides run on moon time, where each day has 24 hours and 50 1/2 minutes, so high and low tides do not occur at the same hour each day. The Time and Tide Clock clearly shows you both tides and the time of day. Time and Tide Clocks are much easier to read than printed tide tables, and come in a variety of styles to compliment any decor. Time and Tide clocks are recommended for use on both Coasts of the United States and Canada. On the Atlantic they never need adjustment. On the Pacific, including Hawaii, they can be calibrated to different coastal locations using our proprietary setting tables. Tide Clocks do not operate in the Gulf of Mexico. Schelling Corp has been making and guaranteeing their Tide Timers since 1971.