We are now manufacturing rugged tailwheels assemblies designed for SuperCub type, back country airplanes. They come with either a 1 1/2" flat tailspring mount (can use 1 1/4" tailspring with a shim) or the tapered round tailspring mount like on a C185. Check out our website for more info: Tailwheels Home Eric Newton - Long beach, MS Bearhawk N57EN