... , Renqiu City, Hebei Province, China. We are a professional manufacturer of oil drilling equipment and accessories based on integrated petroleum machinery ... the technical specifications of the American Petroleum Institute (API6A, 16A) certification and national industrial production permit BOP. Our main products include BOP ... -7/8, 3-1/2, 4, 4-1/2, 5, 5-1/2, 5-3/4, 6-5/8, 7, 7-5/8, 9-5/8, 9-7/8 ...