Catalyst 2960-X FlexStack Plus Stacking Module optional 

Catalyst 4500 E-Series Supervisor 8L-E

Supervisor B for Nexus 9500

1-Port Serial WAN Interface card

4-Port Serial WAN Interface card

Standard airflow pack: N2K-C2348TQ-E, 2DC PS, 3 Fan

Nexus 5672 Chassis Accessory Kit

Nexus 2200 GE FEX FAN, Reversed Airflow (Port side intake)

N2200 GE FEX Fan Module, Std airflow (Port side exhaust)

Fan Tray for Nexus 9504 chassis, Port-side Intake

Nexus 7000 Bottom Support Kit