Hartley Controls 2552 Bond Dtereminator.
Hartley 18PC Control Unit, S/N 18PC-385, D-18PC-989, PLC Panel : Compactibility Unit.
Hartley Compatibility System, with Control, Compatibility Unit-MDL B-2550-101-5, S/NB-2550-263, Bond Determinator, Siemens PLC.
