The Nano-Hone NL-4 Lapping Plate is designed to flatten waterstones from 110μm to 10μm (120grit to 2000grit). See chart here.
The NL-4 is a traditional plated design. However, unlike standard designs, the NL-4 has a raised diamond coated structures.
It is the edges of these raised diamond structures that are doing the heavy work.
The NL-4 has an arrow-rake pattern for heavy material removal. The long straight edges cut very well across stones.
Read instructions here.
9.5 x 2.5 x 0.5 inches
240 x 60 x 20 mm