NQ HQ PQ BQ SURFACE SET IMPREGNATED DRILL RODS CORE BARRELS OVERSHOT HEAD ASSEMBLY ... and assemblies, synthetic diamond core bits, natural diamond surface-set core bit, PDC bits (core or noncoring), casing shoes, reaming ... ,PQ, T2, T6 etc. Diamond core bit, reaming shell & shoe bit (syn. and surface-set, PDC)4.Drill tool: hoisting plug, ... ,etc. Reaming shell BQ NQ HQ PQ, surface set and impregnated