The Poxy-back Attractor (a.k.a. "Trout Crack") represents no specific nymph specie but can match many types of of underwater insects all at once. The rubber legs give it movement, the resin lens on the thorax gives it realism and a glow and the bead and slimmer abdomen profile allow it to sink quickly. This is a great pattern to try as your lead fly in a two fly nymphing set-up. Black available in sizes 6, 8, 12 & 16; Olive in sizes 10, 12, 14 & 16.
TIP: Try the larger sizes (6, 8 & 10) followed by a Sparkle Worm, fished deep during high water/run-off conditions.