Optional at initial order or as field upgrade. Order up to four (or up to two for multi-protocol systems) full height adapters (mix with 10GbE Optical, 10GbE Twinax, 10GBASE-T, 25GbE, or FC) per system. Provides two 25GbE SR, 85c, MMF Duplex SFP transceivers. Includes two 16ft (4.9m) 10GbE optical cables. Requires DXi software version 4.1 or later. Customer installable. Will be installed at no additional charge during system or physical capacity installation. Optional onsite (SDY48-NSYS-000x) or phone-based (SDY48-NSYS-PB00) installation available when only an adapter is being installed.