The Transducer Mounting Hole Machining Tool Kit contains all of the necessary drills and taps to prepare a standard 12 - 20 UNF transducer mounting hole. The kit contains the special pilot drill required to machine the 45 degree seat. All tools included in this kit are made of premium grade, high strength tool steel. Care should be taken in the use of proper speeds and feeds, lubricants, and a method to assure continual alignment of each progressing tool. Consult Dynisco for additional or more specific information. M10 and M18 kits also available.