SINGCALL Wireless Calling System, Service Calling, Home Caring, Can Be Pin on the Wall, Convenient to Press, for Old, Aged People, for Cafe, Hotel, Hospital, Pack of 5 Buttons and 1 Pc Watch Need more watch receivers or pagers? Please search B00EC6P0K8 or B014EPUTM0 on Amazon. APE6600: 01.Directly receive signals of pager(s), convenient to take. Show the time when on standby mode. 02.With sleep mode, saving power and avoid disturbing when do not use. 03.Two prompt modes of vibration or beep, the length of vibration can be set from 1-5 seconds. 04.'Lock the watch' function, can aviod misoperation. 05.Frequently Asked Questions attached in the last page of manual, can solve most problems. APE520: 01.3.39*3.39in flexible square with big round button of 2in diameter, letting simple enlarge fashion. 02.The super big attractive button with 2in diameter, and the sensitive touching reaction , making the calling more convenient. 03.360 degree water-proof handling and the simple pushing bottom base without screws showing the humanized design and making it simple to change batteries. 04.Simple and stable login mode, the phenomenon of messy code does not appear. Signal is stable and long distance. Specifications:2.17*1.77*0.6 inches(55*45*18mm) Us Frequency Range:433MHZ Sound Type:Music/Vibration Standby Time:30 days long With Pager Quantity:999PCS Receiver Sensitivity:-114dbm Power Supply:AAA battery Designing with square and round, owning the simple and fashionable appearance Super big touching button, make calling more convenient. Full water-proof handling and simple pushing bottom base showing the humanized design Simple registration, far transmitting distance Size:3.39*3.39*0.69 inches(86*86*17.5mm) Transmitting distance:130-200ft indoors, 1600ft in the open air Encode and decode mode: registration mode Batteries:Alkaline Battery 12V 23A (*2) Frequency: 433.92MHz Frequency deviation: 0.5 MHz contains screw*2, sticker*1 to fix pager