Dual-port 25GbE SFP28 add-in card for Synology systems



Increase network performance with 25GbE connectivity



Optical SR, Optical LR, and DAC support



Designed for maximum performance and reliability in Synology systems

High-performance connectivity upgrade

Flexible SFP28 options

Support for short-range and long-range transceivers as well as DAC options enables flexible connectivity choices.

Link aggregation

Dual 25GbE ports can be combined into a Link Aggregation Group to boost throughput up to 50 Gb/s, while also providing port failover and load balancing functionality.1

CPU offloading and load balancing

Support for CPU offloading and load balancing technologies enables optimal system performance.

High-performance connectivity upgrade
5-year warranty

5-year warranty

At Synology, we are committed to product innovation and quality. Synology guarantees a robust and reliable data management experience with a 5-year limited warranty, providing responsive technical support and hardware replacement services to maximize your return on investment.2 Learn more

High performance storage systems


  1. Link aggregation increases the total throughput of the network. It does not increase individual transfer speeds.

  2. The warranty period starts from the date of purchase as stated on your purchase receipt. Visit https://www.synology.com/company/legal/warranty for more information.

Hardware Specifications
Host Bus Interface PCIe 3.0 x8
Bracket Height Low Profile and Full Height
Size (Height x Width x Depth) 69 mm x 168 mm x 17.3 mm
Operating Temperature 0°C to 40°C (32°F to 104°F)
Storage Temperature -20°C to 60°C (-5°F to 140°F)
Relative Humidity 5% to 95% RH
Warranty 5 Years
Notes The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)
IEEE Specification Compliance
  • IEEE 802.3ad Link Aggregation
  • IEEE 802.3ae 10Gbps Ethernet
  • IEEE 802.3by 25Gbps Ethernet
Data Transfer Rates 25 Gbps/10 Gbps
Supported Features
  • TCP Segmentation Offload (TSO)
  • Receive Side Scaling (RSS)
  • Generic Segmentation Offload (GSO)
  • 1.5 - 9 KB Jumbo Frame
  • TCP/UDP Checksum Offload
  • Transmit side scaling (TSS)
  • SR-IOV
  • Large receive offload (LRO)
Notes As mixed link speeds are not supported, both network ports must be configured with the same link speed.
Applied Models
Applied Models
  • FS series:FS6400, FS3600, FS3410, FS3400, FS2500
  • HD series:HD6500
  • SA series:SA6400, SA3610, SA3600, SA3410, SA3400D, SA3400, SA3200D
  • UC series:UC3400, UC3200
  • 23 series:RS2423RP+, RS2423+, DS1823xs+
  • 22 series:RS822RP+, RS822+, DS3622xs+, DS2422+
  • 21 series:RS4021xs+, RS3621xs+, RS3621RPxs, RS2821RP+, RS2421RP+, RS2421+, RS1221RP+, RS1221+, DS1821+, DS1621xs+, DS1621+
  • 19 series:RS1619xs+
  • 18 series:RS3618xs
  • 17 series:DS3617xsII, DS3617xs
  • DSM version requirement: 7.1.1-42962 Update 5 or later version
  • For models with an AMD Ryzen V1000 CPU, DSM version 7.2.1-69057 or above is required.


  1. Model specifications are subject to change without prior notice.
  2. The figures are based on Synology internal testing. Each performance test is done individually. No other services or applications are processed at the same time.
  3. The actual performance may be lower than lab testing figure due to differences in server configuration, deployment, and the number of active operations.
  4. If usage requirements exceed the specifications above, please contact our regional partners for professional advice.