168mm Double Head Casing Drilling Bit System Zhuzhou Rockking Engineering Machinery Co., Ltd. Base Info Model NO.：168mmSurface Treatment：Spray-PaintManufacturing Process：ForgingMaterial：Alloy SteelTrademark：ZZROCKKINGTransport Package：Wooden BoxesOrigin：China Description Pre：146mm Double Head Casing Drilling Bit System Next：216mm Double Head Casing Drilling Bit System
