Brand new heavy duty SPST relays12 Volt 30 amp 4-prong relaysMechanical life of 10，000+ cyclesHeavy-duty impact molded relay socket with 4P 4 WIRES Interlocking relay socketsThese are heavy duty 30A relays with metal brackets and wiring harnesses .This kit can be used ti install electric cooling fans，Electric fuel pumps，Electric water Pumps，Shaved door handles solenoids，Trunk solenoids，Horns.Using this kit will eliminate a high voltage drop in the wire，So it allow your components to work properly.Package include: 5 X 30A replay (4Pin) 5 X Relay Socket Wire