S4S material has been surfaced on four sides and sanded. Knotty Alder 1 X 2- Actual Size 3/4" X 1-3/4” Knotty Alder 1 X 3- Actual Size 3/4" X 2-3/4” Knotty Alder 1 X 4- Actual Size 3/4" X 3-1/2” Knotty Alder 1 X 6- Actual Size 3/4" X 5-1/2” Knotty Alder 1 X 8- Actual Size 3/4" X 7-1/4” Knotty Alder 1 X 10- Actual Size 3/4" X 9-1/4” Knotty Alder 1 X 12- Actual Size 3/4" X 11-1/4”