Cost-effective upgrade for Synology NAS and IP-SAN The E10G21-F2 adapter gives you more connectivity options with support for SR and LR transceivers and DAC options. Dual 10GbE ports help alleviate network bandwidth limitations and support Link Aggregation (network bonding) for increased resiliency in the face of network disruptions. CPU offloading technologies reduce network transfer overhead on the host system’s processor to boost system performance.