S3500 Uplink Module with 4 Gigabit Ethernet/10 Gigabit Ethernet SFP/SFP+ (pluggable transceivers ordered separately) for use with S3500-24T, -24P, -48T, -48P, -48PF and -24F. Provides uplinks and ArubaStack interconnects. Includes one 50 cm direct- attach cable (DAC) for ArubaStack.