#10 American March Brown nymphs with #16 Blue-winged olive nymphs. Each double nymph rig selection comes on our foam dropper rig keeper board and Includes 3 double nymph rigs each with 3 larger nymphs as the top or first fly, and 3 smaller nymphs as the bottom or second fly. Smaller size flies are rigged using 5X fluorocarbon tippet between the two flies spaced approximately 19 inches apart. Larger size flies are rigged using 4X fluorocarbon tippet between the two flies with the flies spaced approximately 19 inches apart. The main tippet is approximately two feet long made of 3X fluorocarbon tippet for the small double rig flies and 1X tippet for the larger double rigged flies. Form rigging boards can be reused.