Shapton's Pro (Kuromaku) line prints its own micron from a formula, not a JIS grade, the same as the Glass line. Maker figures (hollow), a single value with no distribution. The Pro ladder differs from Glass: no #500, and it adds #1500, #5000, and #12000.
Each grade below shows its size in microns, its spread (the published distribution, where a maker or standard gives one; most makers publish none), and where that size lands on the reference scale, a shared yardstick for reading grit numbers across makers.