Difference between Single Mode SFP and Multimode SFP
Gigabit Fiber SFP Transceiver SM LC 40km - Fiber Transceivers (SFPs) | StarTech.com United Kingdom
RME MADI SFP Module (Multimode/Singlemode)
SFP MOD, SM, 2.5Gb, 2F, 20Km, LC, 1310nm
TP-Link Gigabit SFP module | 1000Base-LX Single-mode Fiber Mini GBIC Module | Plug and Play | LC/UPC interface | Up to 10km distance (TL-SM311LS): Amazon.co.uk: Business, Industry & Science