Basically a parachute, but designed by Hans van Klinken so that the abdomen ? and tail dip into the water.
Variations abound, but the concept is highly effective.
Fished with single fly .
Standard parachute flies are designed to imitate an insect emerging from the water,
so the body of the fly is suspended in the water surface.
The fly’s hackle gives the impression of the insect’s legs from below and the wing post
acts as a site aid for the fly fisher, as well as holding the fly up in the water