The ChromaKey allows the user to place live video over Amiga graphics. This is in fact the opposite of a genlock which places Amiga graphics over live video. The actors would stand in front a blue screen and the Chromkey would replace any blue colour with the Amiga graphics. Infact some blue cloth was actually supplied with the device, although anything blue could be used. The ChromaKey + was an improved version of the device which worked with the video toaster.