The first one seems tobe a positive ground unit and the current is really not up to the job. The second choice seems to be quite a good unit. Some of these radios require a continuous supply of 12 volts even when the radio is off. This is to maintain a memory.The second unit has that function. I don't think the third unit is a good choice at all.


1951 GMC 1 Ton Flatbed -- It is finally on the road and what a great time I have driving it!
1951 1 Ton Completed


My Chevy Master 4 Door is on the Road!