1.low price 2.high quality 3.full range 4.best ... impact load of the major parts work, such as the axis, small shaft, balance lever, rocker, connecting rod, bolts, nuts, gear ... 0.035P: allow residual content than 0.035Cr: 0.90 ~ 1.20Ni: allow residual content than 0.25 copper Cu: allow ... delivery, delivery status should be indicated in the contract 28Cr4(1.7030) special steel