Theses are, without a doubt, my favorite book markers ever. That's where I am here wanting to buy more. I have two now, and prefer to use this brand rather than any other.
Automatic? Well, that's hard to say. As you turn the page, you slip the turned page under the little metal arm, so that your place is "automatically" marked. It's saved me many nights when I fall asleep reading. Also, you don't have to hold the left side of the book open as the marker essentially does that for you!