Adds Connectivity & Capabilities: Connects up to three high-performance non-GPU PCIe cards via a Thunderbolt 3 cable to your computer lacking expansion slots. Pro Tools HDX Compatible: HDX compatibility mode enables use of up to three Pro Tools HDX PCIe cards with no additional parts needed. Broad PCIe Card Compatibility: Every Thunderbolt 3 compatible, non-GPU card supported regardless of length or height. Three PCIe 3.0 Slots: One x16 plus two x8 slots support three full-height, single-width cards, or one double-width card plus one single-width card. Pro Power Integrated: 400W power supply with 75W auxiliary power. Saves energy by powering on/off automatically with the computer.