Designed to be versatile, sturdy, and easy to use, this bottom board stands alone. It needs no other bottom boards or add-ons to function. A 1/8″ mesh screen covers the entire floor allowing for greatest ventilation and mite drop possible. 3/4″ strips around three sides provide the entrance. This product includes a white vinyl-coated masonite tray that slips in the back on a track below the screen, to monitor mite drop. By using 1 3/8″ stock for two interlocking frames we have achieved a very strong, durable construction. The bottom board and the mite tray can be bought separately as well.