Buy from Amazon.com : http://fave.co/1IhxRc6 <br /> <br />Studiohut Wireless Radio Slave Flash Trigger (4 channel) <br /> <br />Product Description : <br />Low power consumption maintenance cost long battery life <br />LED indicators on both receiver and transmitter There is a test button on top of the transmitter <br />Additional receivers can be purchased and used in multi-flash set-ups <br />Typical battery life of about 20000 usages <br />Maximum effective distance range of approximately 21 yards 20m
