Wireless Calling system advantages:Save labour cost Improve service image Most important, improve efficiency How we use the wireless calling system:First, the calling buttons are pasted or put or on the table, when the guest have any service, he or she the calling buttons, the receiver (LED screen or watch pager) get signal with vibration or sound, showing the table number, then the waiter know which table to be served. Wireless Call Button Transmitter Specification: Call button frequency:433MHz Modulation mode:ASK (AM) Decoding:learning code Working current:17mA Emission Distance:100m (open area) Waiter Wrist Watch Receiver Pager Specification: Power: USB interface Capacity: 500 pcs of call button transmitters Alert Mode: vibration or ring Receive Sensitivity: -110dbm Frequency:433.92MHZ Tips: The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use Colour:B: Black+Blue Material:ABS Package Contents: 1 x watch receiver 5 x call buttons Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.