CB specifications.

So many different radios, which one is the best? Manufacturers and sales staff may throw a load of figures at you, but do you understand the meanings, or just get impressed by high numbers?
How much of the specification is useful for the buyer, how much is standard among all CBs, and how much is just to impress the unsuspecting customer?

Antenna impedance
Audio power
Adjacent channel rejection
Channels.
Conversion system
Current drain
Deviation
Dynamic range
Emission
Frequency deviation
Frequency range
Frequency response
Frequency tolerance
IF
IF rejection
Image rejection
Low power
Modes
Modulation modes
Power source
RF power attenuator
RF power output
Selectivity
Sensitivity
Spurious emissions