Push-pull knobs are a very simple design and can come in many different shapes and sizes and are made for simple functionality where in-out, forward-backward, and up-down motion is required. These knobs are usually made from high quality phenolic plastic polished to a glossy finish, or stainless steel which is perfect for a heavy-duty solution for any clamping and hand fastening needs. Made from high quality phenolic plastic polished to a glossy and typically with a brass insert molded in.