6 Pack of radios and associated accessories Each of our radios comes complete with an external speaker mic, single-unit charger, 15 hour lithium ion battery, swivel belt holster, 1-year warranty Covers up to 250,000 square foot range or 20 floors. Set to factory default UHF frequencies (good for both inside and outside use). RMU2040 is direct replacement to RDU2020 Very reliable, simple, heavy-duty radio that is popular with a variety of different industries.