Seeed Studio 113020011 3V WiFi Module

Grove - UART WiFi V2.0(ESP8285) is a serial transceiver module featuring the ubiquitous ESP8285 IoT SoC. With integrated TCP/IP protocol stack, this module lets your microcontroller interact with WiFi networks with only a few lines of code. Each ESP8266 module comes pre-programmed with an AT command set firmware, meaning you can send simple text commands to control the device. The SoC features integrated WEP, WPA/WPA2, TKIP, AES, and WAPI engines, can act as an access point with DHCP, can join existing WiFi networks and has configurable MAC and IP addresses.

Grove 4-pin connector (RX,TX,VCC,GND)
802.11 b/g/n protocol (2.4GHz)
WiFi Direct (P2P), soft-AP
Supports three modes: AP, STA and AP+STA coexistence mode
Integrated TCP/IP protocol stack
LwIP (lightweight IP)
Integrated low power 32-bit CPU could be reprogrammed as an application processor
Serial UART Interface
Multi-queue QoS management
Wake up and transmit packets in < 2ms
Onboard ceramic antenna