SenMod HC-05 Arduino Wireless Bluetooth Receiver RF Transceiver Module Serial Port Module<div style="text-align: left;"><strong>[Product Information]</strong><ul><li id="replacementPartsFitmentBullet" class="aok-hidden" data-doesntfitmessage="We're not sure this item fits your " data-fitsmessage="This fits your "><span class="a-list-item"><span id="replacementPartsFitmentBulletInner"><a href="#" class="a-link-normal hsx-rpp-fitment-focus">Enter your model number</a>to make sure this fits.</span></span></li><li><span class="a-list-item"> VCC: positive power supply </span></li><li><span class="a-list-item"> GND: power supply is negative </span></li><li><span class="a-list-item"> RXD: the receiver， Bluetooth module receives from another device sent data; normally connected to other devices transmitting end TXD </span></li><li><span class="a-list-item"> TXD: sending end， the Bluetooth module to send data to other devices; receiving terminal is normally connected to other devices RXD </span></li><li><span class="a-list-item"> EN: Enable， then you need to enter the AT mode 3.3V </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/51zuXQIRQdL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/51QDKbDH1BL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41Kx4weBcpL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41l4gHk9yqL.jpg" noproxy>