... ;Frequency: 315MHz,433MHz for option;Available Working Temperature: -20°C - +50°C;Use 2 "AAA"Battery for Transmitter;and 2 "AAA" Battery ... personnel working with you step of the way,from Design,R & D,Mold Making,Toloing Manufacturing,till products are ready to ... part in any country.OEM & ODM are both highly welcomed. Wireless Audio Baby Monitor