Sturdy construction: The four steel support tubes feature a scratch-resistant black powder-coated finish, while the rigid, thick MDF shelves feature a finish that cleans easily and resists scratches and scuffs. Each shelf is acoustically inert and can support up to 75 lbs., while the shelf with the support bar can hold up to 150 lbs. Open air design: The stand is designed with open air shelving for critical airflow, cooling, and ease of access to your components. Unlike most enclosed AV cabinets, this sturdy design will ensure your equipment receives plenty of circulating air that will keep them from overheating during use. Modular construction: The fully customizable modular design lets you build your rack exactly as tall as needed. Start with the base and add as many of the 4 shelves as you need. One set of steel support tubes are longer, allowing one tier of the stand to accommodate taller components. Additional support bar: Attach the provided support bar underneath a shelf for