Cisco Catalyst 2960-X FlexStack Plus hot-swappable stacking module (C2960X-STACK)

Cisco FlexStack-Plus provides stacking of up to eight 2960-X switches with the optional FlexStack-Plus module.
The FlexStack-Plus module is hot swappable and can be added to any Cisco Catalyst 2960-X or Catalyst 2960-XR with a FlexStack-Plus slot. Switches connected to a stack will automatically upgrade to the stack’s Cisco IOS Software version and transparently join the stack without additional intervention.
Cisco FlexStack-Plus and Cisco IOS Software offer true stacking, with all switches in a stack acting as a single switch unit. FlexStack-Plus provides a unified data plane, unified configuration, and single IP address for switch management. The advantages of true stacking include lower total cost of ownership and higher availability through simplified management as well as cross-stack features including EtherChannel, SPAN, and FlexLink.
To provide investment protection, FlexStack-Plus is backwards-compatible with FlexStack. Cisco Catalyst 2960-X LAN Base switches equipped with a FlexStack-Plus module can be stacked with Catalyst 2960-S and 2960-SF LAN Base switches equipped with a FlexStack module