Copper John nymph fishing flies are the hottest nymphing fly patterns on the river. Bead head, slim profile with green copper wire body gets deep in the water column quickly Excellent trout, panfish. bass or steelhead flies. 6 hand tied wet flies hook size 18 Fish singly, in two or three fly nymph rigs, or as a dropper under a foam hopper fly Essential on freestone rivers where insect nymphs are an important trout food. Bead head nymph patterns get down deep quickly to where the trout and their insect nymph prey both live 90% of the time. Bead head nymph patterns also have a nice drift and swim seductively.