Potentiometer 2W Variable Resistor Rheostat Speaker Volume Control 2 Watt B PW24

This is one item of wirewound rheostat available in various values. 

I've classed them as 2 Watt as this is the power rating at which they can be run warm without being mounted on a substantial metal panel. The data sheet states 5 Watts, but after some testing, I would consider this to be a short term overload rating for up to thirty seconds only. The total shaft length is 17mm of which 7mm is the splined turning part and 10mm is the threaded mounting part. The mounting hole required is 9.5mm diameter. The pot body diameter is 25mm. The turning shaft is a standard 6mm T18 splined type.

I have various suitable splined shaft knobs on other listings in my shop.

You may find the 20 ohm type used as a simple loudspeaker volume control connected in series with a four or eight Ohm speaker where the maximum peak music power is 5 Watts. A slightly different arrangement was used to control the front-back speaker balance in a Blaupunkt car radio installation in a 1977 Lanrover.

The track tolerance is +/-20%, rotation angle 300 degrees, and the maximum operating voltage is 120V within the power dissipation limit. The available values are 20 Ohm, 50 Ohm, 100 Ohm, and 200 Ohm.