HT3B to 3.5″ 16ga tube exhaust inlet flange. Which is 3.5″ OD and 3.375″ ID. Bolt pattern is similar to T6 but off slightly. Flange is 3D profiled, CNC machined in-house to maximize air flow. Weldable mild steel. Stud and nut kit to mount the turbo available here https://keatingmachine.com/product/m10-stud-nut-kit/ Also fits many HC4B,HC4C, and HT60 turbos.
