Rotary burr set. Set includes various shapes and sizes, (cones, spheres, tree shape, cylinders etc.) Open tooth pattern for shoveling out materials. Wood, plastics, soft composites. All bits 1/8" shaft size (fitting Dremel, Foredom, Craftsman rotary etc.) These high-speed cutters can be used for shaping, hollowing, grooving, slotting and making tapered holes in soft metals, plastics, soft composites, and wood.