RELM Wireless Over-the-air-programming gives you the ability to reprogram a unit from a central console to anywhere within your coverage area. It allows for you to make the necessary changes to a remote radio without the hassle of extra personnel, wasted time, and additional equipment. “Must have KZA0579”. If you order this with the radio, it will be installed before shipment. If you have a unit that needs this added, you will have to ship us the radio, we will get it installed, and turn it around ASAP.