Benjamin Diabolos
http://www.flickr.com/photos/28168118@N03/2629560264/
http://www.flickr.com/photos/28168118@N03/2629567220/
http://www.flickr.com/photos/28168118@N03/2629605090/

I am really liking this gun aside from having to tighten screws every 50-75 shots...need to buy locktite.

Does anyone know how to rotate the rear leaf?

If you notice I think there is a pin on the back side of the sight if you push in on it a bit should be able to rotate the sight to get the notch you want or to try the 4 different ones. Is it your stock screws that are coming loose on the gun?