The 1520-S is a phenolic pointer control knob designed for instrument and equipment applications requiring manual shaft control. It features a plain hole design with a 1/4" shaft diameter and 5/8" hole depth, accommodating a 1/4" "D" shaft with spring mechanism. The knob is secured using an 8-32 set screw and includes no indicator line marking. This design is ideal for applications in control panels, test equipment, and instrumentation where reliable, durable knob operation is required, offering a cost-effective solution for custom plastic molding applications.