... ,cross bits,rock drilling bit,sandvik,atlas copco high quality carbide cross bits Xiamen Betopper Mining Machinery Co., Ltd. is manufacturer ... , Thread Drill Bits and other Rock Tools.1. Bit Type: carbide cross bits2. Diameter : 28mm - 65mm3. Taper: 6°, 7 °, 11°, 12 ... at regular intervals to crush rock efficiently.We choose different material and size for the taper cross bits in order to ...