Railway Clock
Departments like railways and airports use 24 hour clock systems because they do not use the am-pm system, especially when it deals with travel. The railway clock is large in size so people can see it from far and the numbers are widely spaced out so there isn’t a confusion about where the hand is pointing. You can find a railway clock online if you wish to get one for your home or some other public location, to help people travel on time without having to check their phones or watches all the time.