The KS122 series Expansion Modules can be attached to the KS CPUs or the MK HMI/PLC combo units to expand the I/O beyond the onboard inputs and outputs. The KS series can handle a maximum of 14 expansion modules while the MK can handle 8 modules. Available modules include Digital Outputs Only with Relay or Source Output Types. Each expansion module allows for a distributed installation using a standard Ethernet cable from unit to unit.