Durable star button: These star knobs are made of plastic and brass, not only sturdy to use, but non-conductive and lightweight. Just tighten or loosen it by hand, and you could make a simple protection on your mechanical projects. Star-shaped handle: Using these screw over knob nuts on your mechanical projects can really give you a more comfortable grip. What’s more, you can adjust your machine tools without getting scratched. Brass Female Thread: These Brass Female Thread Clamp Knobs would match the compatible bolt thread very well. Holds well and does not slip. Wide application: These star knobs work well on cabinets, drawers, doors, lockers, tool boxes, appliances, and other furniture or equipment that needs frequent adjustment. Perfectly adapts to your various applications. Widely used in all fields of industry and life, our star buttons would be a good choice for you. Color: Black Quantity delivered: 10 pieces(10 M8x40 star buttons)