Here is table of the 3M™ Scotch-Brite™sanding pads courtesy of Starke Smith. He says that off brands do not work as well.
Color | Grit |
Maroon | 300 to 400 |
Gray | 600 to 700 |
Tan or Gold | 1200 |
White | 2000 to 2500 |
Gray will stain the wood with high friction
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