Villeroy & Boch have two types of flush. If you have two crescent shaped buttons (one bigger than the other), you need to push down the large button and get your fingernail under the smaller one. The button will just flip out. then pull out the larger button. Underneath is a white large flat head screw. Undo to gain access to the cistern. After 2006 they were fitted with a different flush mechanism. The cistern has a large round button with a small square button at the top, you need to just rotate the button anti-clockwise to gain access. You can find spares from bathroomstudio.co.uk
Trevor
January 2009