Roland MV-30 Studio M. I've owned it since 1996. Very well taken cared of living in my home studio it's entire life. Recently I upgraded the LED screen with the expensive SNAFU-Isle of Man LED screen in blue. The wire with the little knob sticking out of the bottom is to adjust the contrast on the upgraded screen. I will leave it out so you can adjust it at your preference and then you can either tuck it back inside or mount it outside. All buttons work. Comes with the OS disk and power supply. These are getting very hard to find.