The ZM-24 2.4GHz Transceiver Module is capable of more than just receiving signals - it can transmit signals as well. This creates a bi- directional communication link between certain RTI control processors and wireless interfaces. The ZM-24 is easy to install, since only one module needs to be hard-wired to the control processor, while additional "repeater" modules can be added by powering them from any electrical outlet within communication range of other modules.