Designed for 19” cabinets these 2U chassis are 88mm high (or 2U). These chassis can accept low profile add-on cards or full height add-on cards via a riser card. Most of these 2U chassis requires a rear fan type ATX power supply or custom sized 2U power supplies. FAN airflow must be out the back. The shorter chassis supports up to micro-ATX sized motherboards and the longer chassis supports up to EATX (including full ATX) motherboards.