CAB-STK-E Stacking cable, 1-m/3.3ft, stack up to 8 switches. Speeds up to 40Gbps on Catalyst 2960-X and 2960-XR using C2960X-STACK Flex Stack Plus or C2960X-HYBRID-STK Flex Stack extended hybrid module. Speeds up to 20Gbps on Catalyst 2960-S and 2960-SF using C2960S-STACK or 2960S-F-STACK Flex Stack Module. Solid connection and Excellent EMI performance. Easy to install, PLUG AND PALY, Hot pluggable. After-sales service: Provides 24/7 Customer Service, 30 Days Free-returned, 1 Year Free Warranty and Lifetime Technology Support