Heavy duty 12V contact relay for electrical isolation of compressor.  

Electric AC compressors have a parasitic current draw of around 70mA.  If you use your car infrequently and do not have a battery tender, this relay can be used with Electrocooler to prevent battery drain.

All Electrocooler ECUs are pre-wired to operate the relay.  Just connect to the grey and black wires to the appropriate spade connectors and run the heavy red cables to the M5 poles.