OK. Micromesh use a different grit size to the standard P range of grits, but 4000 is still very fine indeed, especially when used wet.

Comparison chart here. Micromesh 4000 is comparable to the US 1500 and finer than P2500.

https://www.thesandpaperman.com.au/a...ion-chart.html

I've used Micromesh right up to 12000 before polishing, but in reality, it doesn't make much difference, and you probably spend a lot more time sanding with Micromesh 3200, 3600 and 4000 than you spend applying a few more polishing strokes with a medium polishing compound straight after using P2500.