The superb simplicity of disc meeting shaft at 45° means the seat is unpierced, for the purest of product integrity. The 180° rotation angles the disc cleanly through the product flow so the valve opens without resistance and stays in place. Half a turn of the valve handle provides quick, positive, leak-free shutoff. An "OPEN - CLOSE" mylar label indicates the status at a glance. A Simple twist of the accessory lock-handle transforms the Minidisc® into a regulating valve, locking firmly into any desired position.