Cisco Catalyst 2960S Switch FlexStack Stacking Module for LAN. The FlexStack stack module is hot-swappable and can be added to any Cisco Catalyst 2960-S switch with LAN Base software. FlexStack also allows mixed stacking: 2960-S and 2960-SF switches can be combined to provide a combination of Gigabit and Fast Ethernet ports in a single switch stack.
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