A flicker-fixer and scandoubler board based on the Amber chip found in the A3000. Consequentially this card is often referred to as an Amber Card. Although the card is compatible with models of Amiga, other than the A2000, you may have a small problem physically fitting the card due to its size. A modified "slot cover" can be attached to the back panel of the Amber board to allow it to be mounted securely in an A4000 slot. You'll also need to trim a bit off the "top" of the Amber's metal panel to allow clearance for the A4000 case (a nibbling tool is useful here). Don't remove the enable/disable switch! The Amber gets confused by some of the "doubled" screen modes, and rather than passing them through, tries to double them to 55 kHz or above! On these modes, you'll need the disable switch to force the board to pass the video through.