Ruled surfaces are any surfaces that can be defined entirely by a swept straight line (essentially an infinite number of snapshots of a line as it moves in some fashion). A right conoid is a special ruled surface in that all of the lines that define it perpendicularly intersect the same straight line. If we determine the fixed line to be the Y axis, then this particular shape is created by move a line vertically a distance equal to its height and then back to its starting point, rotating it 360 degrees over that time. I probably didn't need to give that little ten-second math lesson to introduce this product but a little knowledge never hurt anyone, right? This is my new Skeletal Right Conoid, a version of the classic mathematical shape that is reduced to a wireframe in order to better show off its unique structure. Slightly larger than 1.5" in all directions, it's the perfect size to hold in your hand or to keep on a desk. It's unique surface is wonderful to fiddle and play with.