HPE X121 1G SFP RJ45 T Transceiver network media converter 1000 Mbit/s HP Gigabit 1000Base-T Mini-GBIC J8177C is a small form-factor pluggable (SFP) Gigabit copper transceiver that provides a full-duplex Gigabit solution up to 100m on Category 5 or better cable.