[Motorola] What is the Diffenence?

[w7trh at comcast.net]

Hello Group, 



I have a D34LRA7304AK and a D34MJA73A6CK. All I do know is they are UHF 2ch. RADIUS (?). Does the difference in the letters/numbers indicate different options? 



Thanks for any info....... 



Regards, 

Tim W7TRH 

Vashon Is. Wa.