Designed to be used with natural feathers, wing sheet material, foam & other synthetic materials. Handmade in Montana with sharpened razor stainless-steel blades, beautifully grained wood with a hand rubbed Danish oil finish. One set of blades makes 100s and 100s of bodies or wings. Sizes: 8, 10, 12, 14, 16 or 18 (SPECIFY SIZE) OR Set of 6 with matching tool caddy