The Canon Speedlite Transmitter ST-E2 is a compact, hot-shoe mounted infrared transmitter that lets you fire compatible Canon Speedlites off-camera wirelessly. It gives full E-TTL wireless control with Type A EOS cameras and manual flash with Type B cameras, using four channels and two slave groups with A:B ratio control from 1:8 to 8:1 in half steps. High-speed sync is supported, and a test button confirms slave operation. Indoors it reaches about 12-15 m and outdoors about 8-10 m, covering roughly 40 degrees horizontally and 30 degrees vertically. It is ideal for portrait, product and macro photographers who want more creative lighting without the bulk of a master flash. It runs on one battery and weighs about 100 g. After comparing online prices, www.marvel.co.za should be the cheapest on this product.