Features: Brand new and high quality Support PCIe 4.0 devices, backward for PCIe3.0 (using extension cable may leading to slower speed, please consider it before purchasing. ) PCle 4.0 X4 to X16 adapter card with 4X bandwidth. Gold finger technology, 5U thick, using high-density low-impedances circuit board. Adopt new generation GEN4 connector, with buckle, high speed and stability. Suitable for converting X16 card into PCIe X4 slot on motherboards (bandwidth is X4). Support standard PCIe graphics cards, networking cards, ssd, acquisition cards, etc. Specifications: Material:Plastic Type:X4 to X16/X8 to X16/X16 Package Includes: 1x Extension Adapter note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.