The four slots are grouped as two pairs, with each pair consisting of one SFP slot and one SFP+ slot. Each pair supports either two 1-Gigabit SFP modules or one 10-Gigabit SFP+ module. C3KX-NM-10G Network Modules Catalyst 3560-X, 3750-X Series Catalyst 3K-X 10G Network Module option PID The Cisco Catalyst 3750-X Series and 3560-X Series Switches support an optional network module for uplink ports.
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