Montana Fly Co.'s Biot Sparkle Dun in PMD Yellow Orange is a #16 Pale Morning Dun dry fly with a segmented biot body and a trailing sparkle shuck for an emerger-dun profile. The segmented biot body looks like the real insect from below, and the yellow-orange colorway matches the pale yellow-orange PMD duns trout key on during a hatch. The low-riding profile sits in the surface film where selective trout feed — fish it on the surface during a PMD hatch, in riffles, runs, and slow seams. A go-to dun when trout are rising to emergers.