The WWTOP48-BK WorkWise™ Standing Desk Top provides an environmentally friendly work surface for your sit-stand desk. A spacious 48 x 30 inches with a thickness of 0.75 inches, the WWTOP48-BK features mounting holes with threaded inserts that perfectly match Tripp Lite WorkWise Sit-Stand Electric Adjustable-Height Desk Bases, such as WWBASE-BK, WWBASE-GY and WWBASE-WH, for easy assembly. Made and finished in the USA, the MDF (medium-density fibreboard) WWTOP48-BK is constructed entirely of recycled wood fibers with a black low-emission powder-coated finish that qualifies for LEED credits. It's certified by the Sustainable Forestry Initiative and meets California Air Resources Board requirements.