On the undertaking of this task my first assumption was that there would be an easy table to analyze. (I realised on retrospect this is a very clever pun for you woodwork afficionados). However my hopes were dashed *another pun* and i found that merely googling “sandpaper grades” is but to scrape the surface *another* of a deeper, highly complex subject.
Now i could just cheat, stick *pun* a table up on this post with the humungous list of grades and their appropriate grit size.
What ho! I then discover as i slide uncontrollably down a carefully sanded rabbit hole, the list is bigger than one might think. This is the TARDIS of grading lists. You might think that it goes from one end of the spectrum (Coarse) to the other (Fine), but this is to believe that a simple spectrum exists in the intelligence scale. Daft – Clever.
No no no. Because in that scale there would be imbecilic, idiotic, foolish, daft, average, moderate, intelligent, sherlock holmes, dustin hoffman and MENSA. All of a sudden you have a list not of categories but IQ levels. Just so with the grades, this does have a point.
Coarse can exist as several sub-grades but all of which exist in the super-category of Macrogrit. This extends down into the medium / moderate -fine grits (the lower tier of which start to fall into the category of microgrit), and then the system develops a nomenclature method known as fastidious and the furious.
You see, no point in using multiple words when one word will do, with an extra expletive attached for no good reason. Fine – very fine – extra fine – super fine – ultra fine…BUT NO HANG ON. Theres even more in here; fine, very fine, very fine +, extra fine, extra fine +…COME ON.
All i need to know is what not to use on bottom when i’m in the bathroom (turns out the use of sandpaper isn’t recommended in the first place), and what i should be using to remove imperfections from a surface. But instead of this being a simple job it is such to juggle ones sanity and patience, before picking up object-of-which-aforementioned-surface-is-the-surface-of and throwing it into the sea and buying a new one. From IKEA.
Sanded like they would do on Blue Peter – EARLIER. BY SOMEONE ELSE.
Cheers Gary j Mack. Please check your face for signs of sanding.
the FANGG of HORROR ROCK 
I am most impressed with how quickly you analysed the gradients of sandpaper. Not for use on one’s bottom. G
This is the primary take home message. But i do not see this written on the packaging. I intend to sue the company. I shall include pictures of the associated abrasions.