A 50K trimmer potentiometer is a type of adjustable resistor that is used in electronic circuits to fine-tune the resistance value in a circuit. It is called a trimmer potentiometer because it can be adjusted or "trimmed" using a small tool, such as a screwdriver. The "50K" in its name refers to the resistance value of the potentiometer, which is 50,000 ohms. Trimmer potentiometers are usually small in size and are often used in applications where space is limited or where the resistance value needs to be adjustable after the circuit has been built. They are typically used to adjust the gain of an amplifier, the frequency of an oscillator, or the threshold of a comparator.

This small trimpot potentiometer is used to calibtrate circuits by adjusting the value of resistance in the circuit. Trimmer potentiometers require a screwdriver to change the value of resistance and are not indended to by adjusted often such as by the user of the device. Once you have set your resistance value then you will generally leave the trimmer potentiometer at that value indefinitely.