Amazon.com: HP J4858C X121 1Gb SFP SX Transceiver - Small Form-factor Pluggable (SFP) Gigabit SX transceiver that provides a full-duplex Gigabit solution up to 550m (1804ft) on multimode fiber - Has one
NEW TWO (2) HP X121 1G SFP LC SX Transceiver J4858C | eBay
J4858C Genuine HP HP PROCURVE X121 1G SFP LC SX TRANSCEIVER 883585267804 | eBay