... OEM or produce according to your request best service 7° taper drill bitThread button bits1. Rope thread:R25 R28 R32, ... -102MM, T51-127 etc.3. Button bit face design: Flat face, drop centre, Normal and Retrac body.4. Tungsten ... 45mm-127mm);Tapered Button Bit1. Taper: degree 4° ,6°, 7°, 9°,11°, 12°.2. Type: flat bit, cross bit, button bit3 ... used in mining,coaling,metaling and etc 7 taper drill bit