ESP8266 Wifi Shield

Specifications:

• This is a budget Wifi Shield that is recommended for Arduino professionals who can modify the shield with soldering. (for beginners, it's better to get the Yun Shield, ESP8266 IoT Board or MKR1000)
• Fits on Arduino UNO and Mega boards
• ESP8266 Wifi Shield
• Strong wifi connectivity with industrial grade ESP8266-12E serial Wifi module onboard
  
• 3.3V Power regulator onboard
  
• Enhanced PCB antenna for a strong signal
• DIP switch for quickly switching between different operation modes (such as operating mode and upgrade mode)
  
• Integrated serial chip allowing you to quickly flash the firmware
• Stackable design that you can put other shields on top of
• 4 onboard indicator LEDs that display the status of the ESP8266: PWR, DFU, AP, STA
• Usage Notes:
• Soldering is required to remove transistors to RX and TX as described here: https://arduino.stackexchange.com/questions/24919/how-to-connect-wi-fi-shield-esp-12e-esp8266-uart-wifi-wireless-shield-with-ardui
• Once transistors are removed, you can either:
1. Remove all the components in the transistor section beside the text "Designed in" and short across the two transistor pads as described in the link above and use with 3.3V Arduino boards
2. Use the direct access pins on the shield beside the ESP8266-12E module for TX and RX (see ESP8266-12E module pinout in the images above to locate TX and RX) and build a small voltage divider circuit on a breadboard or rewire the switches on the shield as described in the link above.