The open structure of the case is designed to maximize airflow & cooling.> Small test platform with high level flexibility: -Supports 5.25”, 3.5”, 2.5” device -PSU: ATX PS2, EPS PSU -M/B: ATX, m-ATX, Mini-ITX, Pico-ITX, Nano-ITX board Creative M/B clip design for easy installation & un-installation.