SFP copper modules, namely gigabit electrical module, such as H3C models of SFP - GE - T, cisco models of GLC - te. Mouth and SFP optical module on the electrical interfaces are the same (that is, one end of the gold fingers connected to the host), the difference is foreign a mouth with the electricity (i.e. use RJ45 interface), a use of light. Use SFP mouth module can be used on equipment front-end ports, namely by using SFP electrical module convert SFP optical mouth to mouth RJ45 port.