And unlike ham bands, under FCC regs, you are not allowed to build your own GMRS radio, nor alter existing radios to transmit on GMRS, nor modify GMRS radio transmitters. Outside of antenna and coax on mobile/base units, its pure plug and play. The info in the ARRL FCC Tech license book regarding UHF does apply to GMRS, the VHF and band info, not so much.