ESP8266 Serial Wifi Transceiver Module for Arduino UNO R3 ESP-07 V1.0
Arduino UNO R3 and the compatible board can directly connect to this module. 1 x Serial Wifi module. WIFI @ 2.4 GHz, support for WPA / WPA2 security mode. Serial port baud rate: 115200 (default), can be modified to other values by AT command.