The Copper John is a versatile nymph pattern that combines a weighted copper body with a segmented design for realistic movement in the water. Available on barbed hooks in sizes #12 through #22, this fly effectively imitates aquatic insect nymphs and works across a range of stream conditions. The copper construction provides both durability and the subtle flash that triggers strikes from selective trout. Whether you're fishing fast pocket water or slower runs, the Copper John's proven profile makes it an essential addition to any nymph box.