You have to make sure you're getting the right one for your 360. If it's a 203W power brick, it'll fit a Zephyr system, which is the first version of the 360. If it's a 170W power brick, it'll fit a Falcon system, which is the second version.
The 203W brick has a metal connector for what fits in the 360, the 170W is plastic, if I'm remembering correctly.