ESP8266EX 32bit TCP IP WIFI to UART Wireless Module esp8266 Low Power Networking WIFI Module ESP [IC] ESP8266 [Frequency]ï¼?2.4GHz [Distance]ï¼?300m [Interface]ï¼?UART/HSPI/I2C/I2S/IR Remote Control [Introduction]ï¼?ESP-WROOM-02D and ESP-WROOM-02U are ESP8266EX-based modules developed by Espressif. Compared to ESP-WROOM-02, the RF performance of ESP-WROOM-02D and ESP-WROOM-02U are optimized. Besides, ESP-WROOM-02U integrates a U.FL connector. Please see Chapter 8 for details of U.FL connector