Graphite Disc Electrode Specification Spl Grade To Agksp With Ultra F Purity Size 0.492 Inch X Od X 0.125 Inch Id X 0.2 Inch Width Max. Allowable Spot Impurities Per Element - 1Ppm And Total Max Allow Able Spot Impurities - 5Ppm For Oil Spectrometer, Make: Gnr, Italy And Model: Rotoroil Make/Brand: Gnr Or Similar Compatible To Gnr Oil Spectrometer, Model: Rotoroil. [ Warranty Period: 30 Months After The Date Of Delivery ] ]