4.D-Series reliable pneumatic rack and pinion actuators. Designed for operation of plug, butterfly, ball valves, and other 90º turn devices. They are compact and lightweight, making them suitable for installation within areas of tight piping connections.

Bettis D系列可靠的絞齒輪式氣動執行器，是專門用于球閥、蝶閥、旋塞閥等90度回轉的閥門執行機構。它們精巧結實，特別適用安裝在管道連接要求較嚴格的工況下。有雙作用和單作用彈簧回位兩種形式。