This series is a 2 variable resistor with a shaft diameter of 0.2 inches (6 mm) and a diameter of 0.2 Please check the specifications (numerical value) as the image may have differences in shaft length. Variable resistors have a variety of relationships between the rotation angle of the axis and the change in resistance, usually the A-curve, B curve, and rare C curve are used. The A-curve is an exponent change and is ideal for audio volume control (volume adjustment). The B curve can be used to adjust the voltage of general equipment and other applications. The C curve reverses the direction of the rotation of the A curve to adjust the gain of the amplifier. The A feature changes in resistance to the rotation angle of the tap is exponentially and the B feature changes straight. Volume control (volume control) is usually used with a characteristics of A The B feature is not electrically compatible, but when you turn the knob it will change the sound suddenly from one position. There are several types of other categories such as C characteristics in the classification of rotation angle and resistance change, but the demand is mostly A and B. Resistance Change Characteristics: A, Resistance Value: 50 kΩ, Resistance Tolerance: ±20%, Rated Power: 0.06 W, Outer Surface: φ16 mm, Shaft (ΦD x L): φ6 x 15 mm, Axis: Groove, Mechanical Rotation Angle: Usage Temperature Range: Installation: Panel Mounting, Rotation Life: General Purpose, Volume Control (Stereo); Accessories: Screws, Washers. Note: Shaft For the 15mm length, refer to R1610-RB1-A503.