Multi-frequency points: 125 frequency points, meeting the needs of multi-point communication and frequency modulation communication. The two LED lights of the module are the power indicator light (red) and the nRF24L01 status indicator light (blue/green). The built-in watchdog anti-driver program can run stably in industrial control situations with harsh environments. The insertion direction of the nRF24L01 module is as shown in the picture below on the web page. The system not work if it is inserted reversely, but the wireless module not be burned. Using this module for wireless serial communication can make the transmission distance farther (100~1100m, depending on the power of the wireless module used), far exceeding the transmission distance of the Bluetooth serial port Wireless remote control, digital transmission Wireless meter reading system Wireless detection system Wireless data collection system VOIP system Access control system Wireless tag, wireless 232, wireless 422/485 data communication The commands are simple and reliable, and you can communicate without any settings after receiving the goods. System parameters: Support for 98/ME/2000/XP/Server 2003/VISTA/Server 2008/Win7/WIN8 32-bit/64-bit. USB wireless serial port transmission module supports AT to configure the system clearly! Use the stable CH340T chip to convert USB to serial port. Colour:black Material:abs Package Contents: 1 x Debug test socket 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.