国产仑乱老熟女露脸的怀孕的_日韩精品特黄一级片在线观看妓女网香蕉视频_AA级视频在线观看_精品在线免费观看_bbw极度另类孕妇_亚洲AV色一区二区桃_精品无码国模国产在线观看_欧美a级在线现免费_欧美日韩国产其他_日产自拍高清一区

Transporting cylinder chromium plating process the chromium plating layer density reached 300 mesh/was, surface hardness above HV900, generally chromium plating process of chromium plating layer for 60 mesh/was density, thickness of HV700. The company material cylinder thickness of 0.25 mm to 0.32 mm, coating adhesion is extremely strong, not easy to fall off. Fundamentally guarantee the interests of customers, improve the efficient use of the customer.