To Maniac and HoW...
When I got my Ellisimo, I got two walking feet. The other one (not shown) is slimmer than this one - but the guides don't work in it. So that other one is a great for doing seams (like on heavy handbags, totes, etc) ...
But the one above is for quilting with the guide. This one also came with a second closed-sole plate that fits on it.
If you look carefully at the back of this foot, there is a hole on the upper part of the back side that the screw that is on the guide fits through - to tighten it down so it doesn't lose it's setting when you're sewing.
Just wanted to show you this in case you start shopping for a different walking foot.