ST-500 ST-500 is a two/three button type transmitter that is specifically designed to use at warehouse or manufacturing facility. The external antenna attached to ST-500 improves the wireless range. I/II/III version can be registered individually. We are online Now! How can we assist you? WhatsApp Call Now Home » Products » Transmitter » 2/3/8 button bell » ST-500 Related Product Display MonitorSR-A Series PagerSB-700 PagerS-WATCH Light IndicatorSLL-400 Product Detail View PRODUCT SPECIFICATION Description ST-500 is a two/three button type transmitter that is specifically designed to use at warehouse or manufacturing facility. The external antenna attached to ST-500 improves the wireless range. I/II/III version can be registered individually. Specification Number of buttons2 or 3DimensionW55.5 x L99.5 x H15mmWeight55gColorWhite, OrangeFrequencyFSK/433.42MHzBatteryDC 3V coin battery (CR2032)Battery LifeApprox. calling 40,000 timesAntenna TypeHelical antennaCompatibilityAll Syscall receivers and the repeater Features Improve wireless range with the external antenna Wall bracket included Dry contact connection available Benefits Improve service quality Improve business efficiency Increase customer satisfaction Increase business profit System Map Press the call bell when service is needed. The call bell number will be displayed on the receiver with a sound. The direct pager can receive call directly from the transmitters.