Originally Posted by Dan 
It flips up for a normal view. I have one of these on my K20D nearly full time, since it flips up out of the way, but provides unparalleled focusing accuracy with my APO Lanthars. Highly recommended.
Just a quick note to clarify: the photo in this thread does not show how the magnifier flips up over the hot shoe. It really does flip up out of the way.
Dan