2″ x 6″ High Grade Diamond Hone by DMT:
325 grit is for re-doing or re-shaping damaged edges.
600 grit is for honing common tools.
1200 is for getting tools that are in very nearly perfect condition ready for stropping.
(Our tools come perfectly sharp, they should rarely need anything coarser than 1200 grit, as stropping is the principle way to keep them mirror sharp.)