As far as I know they're all pretty much the same. The only difference I can think of is that a power brick and block could just mean the motor assembly with gears and a powered truck would have the wheels attached.
-Brian
OK this will sound a little like Andy Rooney.
Why is it called a power brick?
Sometimes a power block? Are they the same or different?
Powered truck? Is that something all together different?
We do deal with some strange words in this hobby.
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