The Canon EOS 550D is compatible with this ACK-E8 AC power supply. EOS 600D from Canon EOS 650D from Canon EOS 700D from Canon Canon EOS Kiss X4 Canon EOS Kiss X5 Canon EOS Kiss X6i EOS Rebel T2i from Canon EOS Rebel T3i from Canon EOS Rebel T4i from Canon EOS Rebel T5i from Canon The DR-E8 DC coupler allows your camera to be charged continuously, eliminating the need for battery charging. When using this charger, the camera door case must be closed! Excellent for long-term photography, downloading images and videos to your PC, TV, or VCR, and replacing the LP-E8 battery. It is 100% compatible.