The RocketStor 6661A allows you to quickly add any PCIe x4, x8 or x16 card to your Thunderbolt 3 capable computing platform; such as media capture, Ethernet, Fiber Channel, or external Storage/RAID controller cards. Like it's processor, The lightweight, small-footprint design is ideal for compact workstations and mobile computing platforms such as iMacs, MacBook's Pros and Razor notebooks. At just 7 inches tall, and less than 3 inches wide, the RocketStor 6661A is small enough to pack into a laptop bag, yet is capable of supporting full-sized PCIe 3.0 add-in cards.