MFR. Name: Cisco | MFR#: CVR-X2-SFP=
CISCO TWINGIG CONVERTER MODULE
The Cisco TwinGig Converter Module offers investment protection for 10 Gigabit Ethernet switches (such as the Cisco Catalyst 4500, 3750, and 3560 E-Series Switches), by enabling migration from Gigabit Ethernet to 10 Gigabit Ethernet uplinks based upon business needs, without having to upgrade the switches or modules.