... &TB Series Metric Core Bits: T36, TT46, T2-46, TB56, TT56, T2-56, T2-66, T2-76,T2-76 coreline, T2-86 ... . Chinese Standard Metric Core Bits for Single Tube Core Barrels: φ36, φ46, φ56, φ59, φ75, φ91, φ110, φ130, φ160, φ170, φ219, φ27514. Chinese ... Standard Metric Core Bits for Double Tube Core Barrels: φ56, φ59, φ75, φ9115. Chinese Standard Metric Core Bits for Wireline ...