This is a carbon track, single turn, adjustable resistances, of value 1M Ohm Knob potentiometer. It is meant for mounting on panel and is supplied complete with a knob. The knob is affixed on the plastic spindle of the potentiometer and turns the spindle which changes the resistance. The variation of resistance is linearly proportion to the degree of rotation. Potentiometer, in electronic parlance, is a manually variable resistance. Because its most common consumer application is for controlling volume/tone of sound in broadcast receivers, it is loosely referred to as "volume" or ''tone''. It is not a meter with scale and needle. Potentiometers look different depending on size, power handled, application, value and type of material used. There is, however, a common feature-there is wiper which sweeps over a length of resistive material. The two ends of the resistive material as also the wiper are available to the user as electrical terminations. The user gets a variable resistance between the wiper and the two ends.

Also check 16mm size 470k ohm rotary potentiometer, sold in a pack of 5 by Robocraze. The potentiometer has a tolerance of 20% and is designed for adjusting various parameters like voltage and current in electronic circuits. It is a carbon track, single-turn, adjustable resistor with a plastic shaft.