Most quality quiet box fans operate between 25-45 decibels, with the quietest models featuring advanced motor technology and aerodynamic blade designs that minimize noise while maximizing airflow. Siye Motor is a OEM manufacturer covering all process of design, sampling, manufacture, testing, deliver. We will send you performance invoice once we get agreement with you. You can pay us via. Goode Electric is an enterprise specializing in the production, manufacturing and sales of sheet metal parts such as stainless steel and iron distribution boxes and distribution cabinets Our company has a history of more than 20 years and has accumulated rich experience in the sheet metal industry. Hello everyone, today i want to introduce to you the delta ac 220v exhaust fan cabinet power distribution box industrial axial flow fan. Our test in figures: in 2025, we ordered 12 fans ourselves, set them up and tested them in everyday use over several days, including our own dB measurements taken from a distance of 1 metre. The straight-through duct design, with a 180° air outlet direction, better meets the needs of long-distance air supply. The Helios Silent Box (SB) range of Quiet in-line Centrifugal fans, offer a very quiet way to ventilate noise sensitive areas, using ducting up to 400 mm diameter.