Be sure to add me to your favorites list 1980's Vintage Casio Keyboard Slider / Selector / Knob Replacement Spare Part, Very Dark Gray (Nearly Black) with a Red Marker, for Use with Some "MT" and "CT" Models. This is a slider selector / knob from a 1980's era vintage Casio keyboard. These were used on many models to control volume / tempo / effects. This type usually slid horizontally, but there may have been some models that slid up and down too. This kind was often used on some MT models and CT models made in the 80's. Unfortunately, these are very easily lost on some models, so here's a replacement if you needed one! The color of this type is a very dark gray, nearly black, with a red marker on the top of it. The length of this slider is 3/4" inch, the width is fraction over 1/4" inch, and the rectangular tab on the back of it where the stem on your keyboard fits into is 1/4" inches long. Many stems on Casio keyboards will fit into this, but check yours first, or ask and I might be able to help as well. This one is in very good condition, and I have several of them available. Thanks for looking, Check out my Store!