Well, I've always used the basic won-hung-lo alkaline batteries, the store brand, or the Amazon basic batteries, and I generally only look at the back of the clocks in my house twice a year when the time changes occur. I've never had an alkaline battery leak in a clock that I know of.
I have never looked closely but is it even possible to find the older CZ style batteries in stores?
(Personally, I like the clocks that plug into a special recessed wall outlet but I haven't seen any of those sold in a long time! I still see the outlets in houses, often with a battery clock hung over it!
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