B Grade | One piece sanded face with even color. No patches, voids or mineral streaks allowed. |
BB Grade | One piece sanded face with generally even color. Slight pin knots and mineral streaks allowed. Open knots and defects are cut out and replaced with oval patches. |
CP Grade | This is a fall down from BB with more patches on the face that may not always be matched for color. Splits less that 0.5 mm are allowed. |
C Grade | Un-sanded face that allows patches, open knots and veneer splits. |
NOTE: Russian Birch panels are a consistent specie throughout the panel (core and face and back veneer). |