Apart from the trivial 00:00:00, there are 00:55:00, 04:00:40, 04:55:40 and 10:11:01.
using a 24 hours clock we have also 14:11:41, 20:22:02 and also 24:22:42 can be viewed as an answer. Allowing for h:mm:ss formats gives many more solutions.
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