A long time ago we had a special clock with four time zones. We correspond a lot with clients in China. And we often need to keep track of when it will be midnight at the USPTO or at WIPO. The four-zone clock helped us keep track of these things.
But the special clock was noisy. It clicked as the second hand advanced, and somehow the clicks really carried through the office. Not only that, but all four of the clock faces clicked and the clicks were never quite simultaneous across the four faces. So there were 240 clicks per minute. We eventually scrapped that clock.
Now we have a new four-zone clock as you can see in the photograph. The clocks are silent. And the clocks synchronize their time with WWV.
Two of the clocks (the two in the middle) automatically update themselves for Daylight Saving Time. The one on the right will require manual adjustment four times per year (see blog article).