Cisco SFP-10G-SR-S can be used on original Cisco Switch Cisco Catalyst 4948E-F; The Cisco SFP-10G-SR-X is a multirate 10GBASE-SR, 10GBASE-SW and OTU2/OTU2e module for extended operating temperature range. It supports a link length of 26m on standard Fiber Distributed Data Interface (FDDI)-grade multimode fiber (MMF). Using 2000MHz*km MMF (OM3), up to 300m link lengths are possible. Using 4700MHz*km MMF (OM4), up to 400m link lengths are possible