Be sure to add me to your favorites list 1980's Vintage Casio Keyboard Slider / Selector Replacement Spare Part for Some "PT" and "MT" Models. This is a slider selector / knob from an 1980's vintage Casio keyboard. These were used on several of the smaller Casio models, (starting with PT and MT) to control volume / tempo / effects. These usually slid vertically, but there may have been some models that side to side too. Unfortunately, these are very easily lost on some models, so here's a replacement if you needed one. The length of this slider is 18 millimeters long, the width is fraction over 5 millimeters, and the rectangular tab on the back of it where the stem on your keyboard fits into is 4 millimeters long. Many stems on the smaller PT and MT model Casio keyboards will fit this, but check yours first, or ask and I might be able to help as well. This part is a very dark gray, close to black color. This one is in very good condition, and I have several of them available. Thanks for looking, Check out my Store!