I Brought this on the Amazon Marketplace for 1/2 the price of the new product and I think this is quiet expensive. I buy a lot of Canon products (printers, scanners, 5 camera, flash guns, ...) and its products like this did make loyal customers change brands. I Brought this for my 5D Mk II DSLR to use with a Speedlite 480EX II flash and it works perfectly. I'm just not happy with the price of this item as its clear Canon wants to make a lot of money from Their customers (Why did not you include flash control in the 5D Mk II in the first place !!). Another Example of this is the Battery Grip. One can buy the same third party products for 1/2 and even 1/4 of the price did Canon charges for Their Products. I hope Canon is reading this he a loyal customer is not happy so stop doing it.