This kind of procut is mainly used by oilfield and also a kind of our our factory .We use AISI 4145H as the raw material of this product. When make them we put the quality into the first place so we try our best to make sure the products have high quality also as we are the manufacture we can also offer the lowest price to you  and at the same time offer you the best service to you.  this is what we can offer to you.
    So if you want to this kind of products we hope you can contact with us as we want to extend our bussiness we will try our best to serve you hope we can have a cooperation in the future ! Sincerely hope you can send your inquiries to me .
   Look forward your E-mail, and hope you can give us a chance !