This RS PRO 20 mm knob mounts onto your potentiometer shaft so you can adjust voltages in your circuits. It's designed for use with circular, splined potentiometer shafts and is quick to assemble thanks to its push-on design.
For durability, the knob's inner part is made of tough plastic and the knurled aluminium outer shell helps to improve grip. The aluminium is anodised, which improves corrosion resistance and increases durability. There's also a white index line on the black body, which makes it easy to see the knob's position.
This product complies with Restriction of Hazardous Substances (RoHS) requirements, meaning it contains only low amounts of any harmful materials. Potentiometer knobs like this one are often on audio devices to control volume or other types of equipment requiring precise adjustment.