The SB900W hot tub spa air blower has many configurations, filter is an option. It has the function to reduce the high-frequency interference from electric network, quick-dry heater is available; ozone generator and speed-adjustable PCB are available, with the characteristics of large air flow, large air pressure, low noise, easy installation, long life. They are double impeller air blowers. The casing is high reinforce and high temperature resistant engineering plastic. They are the best choice products for small hydromassage bathtub and SPA large pool making bubble.