Below you can see a newly re-enamelled post-74 'Deluxe' Aga range cooker hob and lids. The hob is the single flat section that fits around the hotplates and flue. It must be lifted in above the hotplate and dropped down onto the front, back and sides of the cooker on which it sits. It is secured onto 'tie' rods that go right down to the bottom of the cooker by hob screws. The hob caps screw into these to finish the look. The hinge blocks are always re-enamelled along with the towel rail brackets and towel rail replaced.
Power flue gas and '30amp' post-74 cookers have a raised shroud that runs along the back of the hob behind the lids. This contains the extra fans and electronics required for the operation of these models. You can see the shroud clearly in the pic below of a '30amp' cooker. You can find more information on our 'What model Aga range cooker do I have?' page.