Keep in mind our catalog is catered to pro shops even though we sell to individuals as well.

The reason you would have multiple cab blocks would be if you have a resurfacing machine.  You would then have 8 sets of cab blocks to switch out.  Being color coded makes it easier to keep track of what grits are on the blocks.  If you just have a ball spinner I would recommend having one cab block of any color and switching out the grits as necessary.  The grits come in 9 packs for resurfacing machines to give you 3 rounds of use.
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Russ Wilson
Brunswick Amateur Staff
Pro Shop Manager
Jayhawk Bowling Supply
www.jayhawkbowling.com

Yup:

TRIZACT GRIT CHART (Courtesy of Charlest)
A long while back when this confusion first arose I sent an email query to 3M who invented Trizact and manufactures it. This is their answer:
To extrapolate the micron to grit conversion from 3M:
A35 ~ 35 micron ~ 360 grit,
A10 ~ 10 micron ~ 1100 grit
A5 ~ 5 micron ~ 1600 grit
Trizact and micron(u) grading are two separate things. Trizact products
are graded on their own scale ranging from A6 - A160.
3M Superabrasives are micron graded, that is, measuring the average size
of an individual particle on that product.
Standard abrasive grading is based on the screen mesh used to separate
out the particles for a particle grade. In simplest terms, in a 1"
line of grade 24 product there are ~24 particles. In a 1" line of
grade 600 product there are ~600 particles.
In comparison, 9u=1200 grit, 15u=600, 20u=500, 30u=400, 40u=320
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DizzyFugu - Reporting from Germany

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Just buy one Cab and Abralon pads and some of the discs that Valentino's sell's add in a group of every color scotchbrite and you are set for life.