Features 3 CHANNELS --- The AM transmitter is 3 channels design, with frequency of 1MHZ, 3MHZ, and 5MHZ, with less interference between channels. 1 METER DISTANCE --- Micro power transmission, at a distance of about 1 meter, with stable transmission performance, safe and reliable. APPLICABLE FIELD --- This AM transmitter can be used for radio receiver player testing and experimentation, with a wide range of applications. BATTERY POWERED --- The amplitude modulation transmitter is powered by a battery (not included), simple and convenient, can be used at any time. COMPACT SIZE --- The AM transmitter has a compact size for easy installation and use, and excellent PCB ensures efficient operation. Specification: Item Type: AM Transmitter Material: PCB Working Voltage: 3.6V Working Frequency: 5MHz Product Size: Approx. 10 x 5mm / 0.4 x 0.2in Power Supply: 1 x Battery (battery not included) Package List:1 x AM Transmitter 1 x Antenna1 x Audio Cable   Note:Battery is not provided and need to be equipped by the user. Package List 1 x AM Transmitter 1 x Antenna 1 x Audio Cable