1, Used for rock drilling 2, High quality&reasonable price 3,Certificate ISO9001 ... stone machines. Our products are well sold all over the China. and also export to USA , Japan, Canada, Australia, ... approval of the customers. . Bit face designsApplicationsButton bit, short skirt For H22 drill rodButton bit, long skirt For H22 drill ... hard rockWaiting for your inquiry!! High pressure Rock Drilling Bit