The ASUS A21 micro-ATX case supports up to 360 mm radiators, graphics cards up to 380 mm in length and CPU air coolers up to 165 mm in height. The front-panel mesh is 40% porous to maximize the balance of airflow, dust filtering and RGB visibility. The A21 provides a compartment behind the motherboard that is 33 mm wide to keep your wiring tucked away and tidy.