It's a modular body tied on a thin #10 beading needle (google John James beading needle). Needle rubbed with purple cross country ski wax.
A dozen wraps in one spot allows thread to hang. Lash down a duck flank feather with feather tips matching needle tip, from front to back with wide loose turns, also lashing down tail fibers and a quill as you go. then back to head again, also with wide loose wraps.
Wet the feather body foundation slightly with fabric cement. Wind the quill.
A long skinny strand of Senyo Laser Dub makes the wing. Pull it up either side of the body. Tie it off with one or two parachute wraps (pull up on the wing as you wind, changing hands as needed). Whip finish in front of the wing with three wraps at most.
Pull it off the needle with both hands. One hand pinches the body, so it doesn't compress as the other hand pushes the whole assembly off the waxy needle.
Wet the bottom of the wing area slightly, with fabric cement.
Lash a hackle feather onto a short shank light wire emerger hook. Now mount the modular body with perhaps 3 very LOOSE wraps. Pull up on the wing with one hand. With the other two hands wind horizontally, between body and shank, to both tighten things up a bit and to build up a slightly vertical thread post, between body and shank.
Wind the parachute hackle, between body and shank.
Leave bobbin and hackle pliers hanging. Turn vise so fly is on its side, with bottom of thorax facing you.
Put a micro dab of UV or CA glue at the fulcrum of the parachute. Pull down on the dangling thread and feather with one hand while pushing a razor to the base, immediately below the parachute. It's done.
Casts well. Lands gently and upright every time. Floats well. Dries off quickly, with maybe two sharp snap casts.
Catskill flies--I've noticed--do not always land upright. This one does. It probably doesn't really matter. But it is interesting. Catskill flies never land upside down. But they do--oftenly--land on one side or the other, rather than right side up.