On-board N76E003/STM8S003 and ESP-01 WIFI module Mode 1: Cell phones carry on the wifi module directly Mode 2: Cell phone and wifi module carry on the same router Additional function: As an USB relay module when unplug the ESP-01 In the open environment, the maximum transmission distance is 100m when the cell phone carry on the wifi module directly ; When the wifi module and cell phone carrying on the same router ,the transmission distance depend on the router’s signal intensity; Use Smartconfig technology of ESP8266 to configurate the password for the ESP-01 module with APP On-board 12V, 10 A / 250 v AC 10 A / 30 v DC relay, absorb 100000 times continuously, Module with diode effusion protection, short response time On-board model selection and working position indicator LED On-board preserved UART debug interface and MCU program interface, Manufacturer: DollaTek