xStack 20-port SFP Layer 3 Stackable Managed Gigabit Switch including 4-port Combo 1000BaseT/SFP plus 4 10GE SFP+ - Including 4 built-in Combo 1000BaseT SFP+ ports - 4 10GE SFP+, 80Gbps physical stacking bandwidth - Switching Capacity 128 Gbps - Packet Forwarding Rate 95.24 Mpps - Up to 9 units per stack with other DGS-3630 series switches - Up to 32 units per Virtual Stacking/Clustering (Single IP Management) up to 20Gbps stacking bandwidth - IEEE 802.3ah Ethernet First Mile(EFM), IEEE 802.1ag/ITU-T Y.1731 OAM - MTBF 280,612.09 hours - Weight 3.78kg - Dimensions 441x259x44mm.