SINGCALL Wireless Calling System,New Generation Watch Receiver,Big Screen,Easy to Use,Support User-defined,Rechargeable Lithium Battery, Watch Receiver(APE6800) 1. Big color OLED screen, thinner, lighter and more flexible anti-seismic and knock, can bear low temperature, self-luminous, big visual angle, can see the information clearly. Do not need backlighting, low energy consumption 2. Rechargeable design, avoiding the trouble of changing batteries frequently, long stand-by time (about 10 days). 3. With encryption function, avoiding information lost by mistake operation. 4. With fast delete function, can delete the one or all calling information by one button. 5. Assorted with charged software, users can define the showing information, advertisement information and colors. Can also make registration more simple. Frequency: 433.92MHz Work temperature:30-120 Specification: 1.57*2.05*0.59 inches(40*52*15mm) Function keys: DOWN, ENT, FUN Number of display: Display one group number and store 10 numbers scrolling display. Battery: Rechargeable lithium battery Call button/pager capability: 399 Prompt mode: vibration, beeper, vibration&amp;beeper Number deleting mode: manually, automatically Screen: Color OLED Display resolution: 128*128 Receiver sensibility: -114dBm (For the multi-button pagers, the mantissa on the right means different call functions, 01 means Order, 02 means Drinks/Water, 06 means Service, 08 means Bill. For example, 001-06 means that 001 is paging for Service. 007-08 means that 007 is paging for Bill. When the key Cancel of the pager is pressed, the calling number on the screen disappears and it means the service is done. Also show the functions&#039; name under the number)