【PACKING LIST】 : Ø30 mm, 40 mm, 50 mm drill bits, SDS+ mandrels, pilot drill and SDS+ 350 mm extension rod; This high-quality TCT concrete hole saw set contains everything you need to get started. 【Necessary parts included in delivery】: This core drill bit set comes with 1 locking screw and 1 pilot drill bit, which is very convenient to stabilize the drilling process. Make sure the tip of the drill bit does not move when drilling. 【PREMIUM MATERIAL】: This masonry cutter set is made of high quality material with tungsten carbide tip, high strength and excellent drilling performance for long-term difficult drilling work, also durable enough. 【PRECISE CUT】These are tungsten carbide tipped drill bits that are perfect for cutting clean holes in concrete, brick and cinder blocks. 【WIDE USE】Suitable for brick walls, red bricks, masonry, foam bricks, hollow cores, etc. It can be used to install air conditioning systems, such as air conditioners, range hoods or washing machines. Note: Do not