The Hammond CU-1 Tremolo/Chorale Switch is specifically designed for the Hammond XK-3c organ and works best with Hammond digital keyboards like the SK-2,SK, and XK1-C series.
it is basically brand new, I bought it for my XK1-C, but I sold the keyboard. This unit* gives you convenient control over rotary speaker speed
Made for use with the Hammond XK-3 organ
Will control the digital Leslie effect on the XK-3, or any Leslie speaker connected to your 11-pin speaker connection.
Mounts on front rail of XK-3
Includes 2 screws for easy mounting