Pennwood Unfinished Red Oak Solid Hardwood 11/32 in. Thick x 7.5 in. Wide x 36 in. Length Retrofit Riser, $16.99 USD/Box, LL Flooring (Lumber Liquidators)

Designed to fit the face of a stair riser, this piece matches the lower stair tread or hardwood floor. This riser measures 11/32 inches thick by 7.5 inches wide and 36 inches long, and is sold unfinished in boxes.