Discover Hidden Potential ASUS A21 is a computer enclosure designed for users who make minimalist, mainstream systems, offering support for different AIO-type cooling systems and graphics cards and high air flow performance to ensure seamless operation. Although A21 is a micro ATX enclosure, it supports coolers up to 360 mm long, graphics cards up to 380 mm long, and air cooling systems to a 165 mm high processor. This gives users many options when submitting a new computer. Efficient and Optimal The grid surface of the front panel of the A21 housing has a permeability of 40%, which provides the maximum balance between effective airflow and RGB lighting visibility. Users can install up to three 120 mm fans in this section of the system to effectively maintain a low computer temperature. A21 provides a storage compartment behind a 33 mm wide motherboard that will help you hide the cables and ensure an orderly appearance.