ETag Quasar reader/writers are used for access control and a wide variety of automatic identification and data collection applications. Compliant with ISO 15693 standards, these high frequency 13 MHz units offer the latest in open architecture and interoperability. The ET4-WXM and ET4-WXS units have been optimized for use in access control applications. An industry-standard Wiegand interface allows easy connection to control panels by most manufacturers. Bi-color LED and buzzer control are also provided. An RS-485 communications protocol is included. This permits two-way data transfer for read/write applications. Used with, or instead of, the Wiegand communications, RS-485 offers the systems integrator unique opportunities for merging access control and other systems.