Frank Sawyer's Pheasant tail nymph is a well known pattern that has been copied worldwide in numerous and diverse imitation flavors: with
bead head, with legs, with shiny thorax, etc.
But there are good and valid reasons
to stick to Frank Sawyer's original design and true dressing of the PTN, even if all the modern variations may catch more anglers.
Frank Sawyer was a passionate, self-taught entomologist, he inspired his dressings by observing the real insects through the microscope.