This Peugeot mill has 6 pre-set grind levels, which are marked on the base, and it can be adjusted to any level in between. The lowest level can consistently produce an extra fine grind, almost dust-like.
The wooden adjustment dial on the bottom can get affected by moisture. If used in the kitchen, this mill should be wiped dry after every use, because frequent exposure to water/steam can cause swelling and splitting of the adjustment dial.
The Cole & Mason Derwent pepper mill has six preset grind levels, clearly marked and easily adjusted by turning the base dial. It can consistently grind peppercorn at a fine level, as well as at a very coarse one.