1, board square generally refers to a kind of wood-like board synthesized from wood or compounds with easy texture, heat resistance, fire resistance, waterproof and moisture resistance. It is the floorboard and square timber sawn longitudinally from logs.

2. The width after processing is greater than 3 times the thickness, and the width is less than or equal to 3 times the thickness.

3. Plate purlin is a common material in furniture manufacturing and civil engineering.