Full Calf Tail– natural and beautifully dyed colors available from Wapsi, Hareline and Metz. Calf tail is one of the most useful fly tying materials you can own. Calf tail unlike bucktail is medium in length, fine, and the hair more crinkly than bucktail and other hair patterns. Calf tail Can be stacked for use on dry flies such as comparaduns or green drake cripples, steelhead top water and tradition style swing flies, and saltwater patterns.