... cone offset, results in high bit penetration rates.4)The deep intermesh of cutter rows prevents bit balling in sticky formations ... /2",7 1/2",7 7/8",8 1/2",9 1/2",9 5/8",9 7/8",12 1/4",14 3 ... to minimum.Main Type AvailableSize: 8 1/2",9 1/2",9 5/8",9 7/8",10 5/8",12 1/4", etc ... Type AvailableSize: 2 3/8",3",3 5/8:",3 7/8",4",4 1/2",4 5/8",4 3/4",6",6 ... 1/2",7 1/2",8 1/2",9 1/2",9 5/8",9 7/8",12 1/4",15",15 ...