Features: 2.4GHz digital wireless transmission, stable transmission signal. Built-in MIC and speaker for two-way audio monitoring. High sensitivity, the crying voice is easy to be heard and the lamp will turn on to inform parents. Position the transmitter at a distance of about 1.5-2.0 meters from the baby. Open space transmission range up to 250M. VOX function. With 2-way talk , music and nightlight function. Specifications: Transmission Frequency: Ism 2400-2480MHz Transmission Power: 17dBm Modulation Type: FSK Power Supply: DC5V 1A Battery: 3 * 1.5V AAA (not included) Power Consumption: 70mA Operating Temperature range: -10~+60 Storage Temperature: -40~+70 Material: plastic Baby Unit: 62*35*111mm Parent Unit: 62*42*111mm (with clip) Package Size: 17.3 * 15.6 * 7cm / 6.8 * 6.1 * 2.8in Package Weight: 285g / 10oz Package List: 1 * Transmitter 1 * Receiver 2 * Power Cable 1 * User Manual (English)