The locking beaks do not line up with the striker.The reasons for this happening are: Fitting template has not been followed correctly and striker height needs adjustment. Fitting template has not been followed correctly and holes for lock body are out of position. Because of the different types of door sections in both timber & aluminium, there may be a requirement for an extra width striker or a striker or lock body packer. The key and internal turn snib are hard to operate.When fitting the lock rather than using the recommended 10mm drill bit when drilling holes for the lock body, an undersize hole has been drilled. This will cause the cylinder turn bar to bind on edges of the drill hole. I have fitted the Onyx from the display pack and it appears to be working correctly, but there are many parts left over.There are extra parts provided in the retail display pack because of all the different door sections and configurations in the marketplace.