Neptune Systems DOS QuietDrive Dosing PumpDS QuietDrive Dose. Automate. Protect. New QuietZone Modes for Reduced Noise New Continuous Duty Modes Same Reliable DS Hardware Compatible with A2 and A3 Series Apex Controllers In the most important ways, this is still the same Neptune Systems DS that reefers have come to know and love. The Neptune Systems DS QuietDrive remains a highly efficient, programmable dosing system designed to work seamlessly with the Neptune Systems Apex Controllers. Ideal