Features: _x000D_ Scope of use: air conditioning drilling, wall drilling coring, range hood drilling, engineering bridge drilling, construction drilling coring, machine room pipe, etc _x000D_ Standard hex joint, high quality screw hole interface, convenient for loading and unloading drill bits _x000D_ High strength seamless steel tube substrate with high hardness, not easy to deformation,and wear-resistant _x000D_ Sharp edge, thick diamond, wear - resistant, sharp, and not easy to defect _x000D_ Fast drilling , sharp and tough, labor - saving safety, high stability _x000D_ _x000D_ _x000D_ Specification: _x000D_ Material: Diamond _x000D_ Name:Wet Diamond Core Drill Bit _x000D_ Type:51*370, 56*370, 63*370, 71*370(Optional) _x000D_ _x000D_ Package list: _x000D_ 1 x Wet Diamond Core Drill Bit _x000D_ _x000D_ _x000D_ Note: _x000D_ Water drill: water must be added in the process of use, and it should be used for core-cutting project. It is suggested to be matched with fixed or hand-held drill _x000D_ Drill bit installation: firstly, check whether the spindle is swinging and whether the electrical and mechanical parts are normal. Drill bit is loaded to ensure that the drill bit is clamped with the drill and remains concentric._x000D_ Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.