... are primarily used in deep coring. With an overshot device, they eliminate the need to couple ... is retrieved. Available sizes in AQ, BQ, RQ, NQ, HQ, and PQ. T2 Series Double Tube Core ... bits & Casing shoe bits Surface-set diamond reaming shell NQ & HQ impregnated diamond core bit 6mm & 12mm Drill ... ( { 'aImgSrc': aBigImageSrc } ); } )(); Core barrel assembly NQ, HQ, PQ, NQTT, HQWL, T2, T6, NMLC, HMLC