... 3.high quality and reasonable price 1) taper angle(degree): 4.46, 6, 7 , 11, 122) shank size: hex 22mm* ... used. A 7-degree angle can also be used if bit spinning is a problem when using 11 and 12-degree ... equipment. In addition, a 4,46 degree angle is ideal for soft rock when you ... under collar(mm): 400 800 1600 2400 3200 4000 48004) Bit diameter(mm):29,30,31,32,33,34,35,36 ...