Cross-Reference Charts

Type of Finishes

Current SPI
Finish Numbers

Roughness Comparison R.A.

 Diamond

#3 Diamond Buff

A1

0-1

#6 Diamond Buff

A2

1-2

#15 Diamond Buff

A3

2-3

 Paper

600 Grit

B1

2-3

400 Grit

B2

4-5

320 Grit

B3

9-10

Stone

600 Stone

C1

10-12

400 Stone

C2

25-28

320 Stone

C3

38-42

Dry Blasted

#11 Glass Bead

D1

10-12

240 Aluminum Oxide Blast

D2

26-32

#24 Aluminum Oxide Blast

D3

190-230