【QUALITY MATERIAL】: This masonry hole cutter set is made of high quality tungsten carbide tipped material, high strength and excellent drilling performance for long term hard drilling work, also durable enough to serve a long service life 【6 SIZES】Includes 35, 40, 50, 65, 80 and 110mm core drill bits, SDS+ arbors, guide drills and 350mm SDS+ extension rod. This high quality TCT concrete hole saw set contains everything you need to get started. 【FUNCTION】These are tungsten carbide core drill bits that are perfect for drilling clean holes in concrete, brick and block. 【USAGES】35mm-45mm drill bits are used for drilling water and heating pipes, 55mm-80mm drill bits are used for air conditioning pipes and 110mm drill bits are used for 4 inch wall fans. 【PACKAGE INCLUDED】Comes with 2 set screws, 2 pilot drill bits, 6 x core drill bits, 1 x 110mm shank and 1 x 350mm shank.