The Cisco STACK‑T3‑3M is an original 3-meter Type 3 stacking cable for Cisco Catalyst 9300L and 9300LM Series Switches. It enables the connection of multiple switches into a single logical stack and supports Cisco StackWise‑320 technology with up to 320 Gbit/s stacking bandwidth.

The cable is used to connect multiple switches in a ring or daisy-chain topology, thereby improving network scalability, redundancy, and manageability. The stack behaves like a single switch with a shared management IP, a unified configuration, and the ability to add or remove switches during operation (hot-swapping).