My mistake, the letters on the dial there only say "PARK O METER" which is the only reason I knew the brand.
Around that, there are numbers arranged like a clock. The smaller inner dial turns and has a hoop so you can select a number, and then the inner knob has a pointer that will do the same, which is why I assume it's meant to mark what time you dropped change in.
The other device is a spring-loaded thing. One side perfectly fits quarters and could probably hold a couple dollars worth of quarters, and the other side looks like it holds nickels or dimes.
As for the size, the keyboard its on is pretty good for judging the size. definitely pocket sized.