The 2830-A is a four-arm phenolic knob designed for manual control and adjustment in industrial and mechanical applications. It features a phenolic plastic body with a brass threaded insert and steel zinc-plated projecting stud, providing durability and corrosion resistance. The knob is configured with a 5/16-18 threaded insert at a depth of 1/2 inch, allowing secure mounting and reliable engagement. The phenolic material offers excellent electrical insulation properties and resistance to wear, making it suitable for control panels, machinery, and equipment requiring ergonomic manual operation. This knob design is commonly used in industrial equipment, laboratory instruments, and consumer appliances where a robust, easy-to-grip control interface is needed.