Exclusively designed by Phoenix Phase Converters, Automatically connects another phase converter in the system, also can be used to turn only one converter on at a time. Designed for convenience and saftey if you forget to leave the joining phase converter or disconnect in the ON position while starting the first converter, it can put too much load on the first phase converter the AutoLink box will prevent this, also the convenience of the AuotoLink Box will automatically pair the three phase together. can also be used to join a transformer online instead of another phase converter.