Solid one-piece high torque durable stem. Tight stem-to-ball directional engagement, ensures relief hole alignment. Strict materials and manufacturing tolerances control. Narrow space between extension ID and stem OD allows the stem seal to remain at an ambient temperature. Relief hole on the upstream sphere of the ball to prevent pressure build-up in the cavity. Up to 45° from vertical for 12” bonnet (per BS6364 guidelines). Up to 15° from vertical 6” bonnet (not BS6364 compliant).