Although a single ISA 430 MKII can act only as a mono or split mono unit, it's possible to link two ISA 430 MKIIs together for stereo operation.
Using a single stereo TRS jack cable to connect the 'dynamic link' sockets on the rear panel allows for stereo operation of the compressor, plus dual mono EQ, controlled from just one of the units.
Please see the "Dynamic Link" section of the User Guide which is available from the Downloads section of our website.