... parameter:ModelHZ-2507A PHR Protable rockwell hardness gaugeHardness scaleRockweel—A, B , C , D , E , F , G , H , KSuperficial rockwell—15N ... 8"AccuracyMeet GB/T230.2-2004 (see instructions in Appendix B); ASTM E18; ISO6508-1Rockwell hardness scale choice:The tested ... phosphor bronze, malleable iron, etc. (HRB value of nearly 100 materials).1/16 steel ballG150BAluminum, zinc, lead and soft metals ...