None of the 12 are marked (as the one reviewer pointed out...the finer sponges are hard to differentiate) but if marked, the cost would go up.2

Great value for the money, sponges are great for touch ups around the house!

It appears that I have have 2 coarse, 6 medium and 4 fine sponges.

Not as good as the sanding sponges I got at HD.

It turns out that the 3M 400 grit ("extra fine") sponges are not much different than these 400 grit ones.

Excellent sanding sponges

I added a star because they are actually really nice sanding sponges and do a good job

None of the 12 are marked (as the one reviewer pointed out...the finer sponges are hard to differentiate) but if marked, the cost would go up.2

but if your sanding sculptures with odd edges/angles like me, you spend the extra cash to get the name brand more durable sanding sponges.