The Tire Router Kit, No. CBTR-KIT1, from Mac Tools is designed for use in the rubber vulcanization process and allows full control on convex surfaces. Its cone endpoint allows the pierced hole to be enlarged to stem size, while the flute geometry offers an effective method of grinding rubber and steel belt sections.Included in this kit is the 1/8” by 2” Tire Router, No. CBTTR1; the 1/4" by 2-1/2" Tire Router, No. CBTR2; the 5/16” by 4-1/2" Tire Router, No. CBTR3; and the 3/8” by 4-1/2" Tire Router, No. CBTR4.