This is a 1k Sliding Linear Potentiometer. Linear Potentiometers are variable resistors whose resistance can be varied by moving the handle linearly from one end to another. The sliding potentiometer has two ends which means when the handle is at one end the resistance is 0 ohms and moving the handle towards the other end will change the resistance towards 1K as per the handle movement. The potentiometer comes with a plastic knob which gives the best feel for usage.