Threader fly box for the smallest of fly sizes #20 – #32. Seven rows of Micro Slit Foam in the base hold up to 161 flies, while the lid contains three compartments with Magic Fly Sheets to prevent flies from blowing out. Also included are two ultra midge threaders, a white background for seeing hook eyes easily, and a clip holder for a C&F nail knot pipe (sold separately). Spare threaders are available separately.