5/8 plywood used for concrete forms. for the 18 inch wide(high) used forms there is 11 pieces in 8 foot lengths and 10 of shorter 5 foot pieces and 8 of shorter 3 foot pieces. there is also 17 pieces that are 12 inch wide and 8 feet long that were not used for forms and would work great for shelves. $8 each for the biggest or make an offer. all in good shape.