This product is either discontinued or we cannot get that from suppliers.
Synology E10G18-T2, Data Transfer Rates 10 Gbps, FF Plug-in card - low profile, 2 x 10Gb Ethernet (RJ45), PCIe 3.0 x8 (Full-Height/Low-Profile Slot), 802.3ab, 802.3ad, 802.3an, 802.3x, 9000 Bytes, Full-Duplex Mode: 10 Gb/s.
Add a pair of 10 Gb/s Ethernet ports to a Synology NAS server with the E10G18-T2 Dual-Port 10 Gb/s PCIe Expansion Card from Synology. Equipped with a PCIe 3.0 x8 interface, the E10G18-T2 expansion card comes with two 10 Gb/s RJ45 ports.