Tri-metal Electrical Contacts: Ag\Cu\Ag,FAg\Cu\FAg ,AgNi\Cu\AgNi ,AgSnO2\Cu\ AgSnO2 AgSn02In03\Cu\ AgSn02In03,AgCu\Cu\ AgCu,AgZn0\Cu\ AgZn0,AgCd0\Cu\ AgCd0,etc. The bottom weldable layer from a material with higher electrical resistivity such as steel,nickel or copper-nickel alloy. To improve the Welding process,the underside often have an embossed pattern with 5 to 7 weld projections. widely used in micro switches,thermostat,keys and breakers protector. Tri-metal Contact has contact surface materials as Silver ,Fine Silver ,AgNi,AgInSnO2, AgCu,gZnO, AgCdO etc. Its base material as CuNi,Fe,Fag\Cu\Fe,AgNi\Cu\Fe,AgSnO2\Cu\Fe,AgCdO\Cu\Fe,etc. Its characteristic as follows: 1.Tri-metal contact has a contact surface as Fe material ,with small convexes to increase welding. It helps the welding stability of contact with bi metal sheet and stainless steel sheet base materials etc. 2.Welding position is bonded by melting metals. Its electrical stability is much better than riveting contact with its perfect image and position ,If riveting ,may commonly distort bi metal in too lose welding .Later it influences temperature meter with data deviation . 3.By comparison with Welding Contact ,it has short heat time and clean environment .It is available for mini part producing ,especially for mini system . Tri-metal Contact may select different silver alloy metal by different electricity currency in appliance .It is available for contact bridge conjunction by electricity pulse welding .It is used widely for contact parts making and bi metal bridge ,such as relay ,mini –switch ,thermal controller ,button and circuit breaker. Tri-metal Contact product line composes roller automaton ,extruder machine ,welding machine ,auto stamper ,sheet contact machine ,hydraulic pressure tester, projector ,microscope etc .about 100tesing machine. It can make contact product per customer design with annual output 2 billion pieces capacity .