FREE SHIPPING TO CUSTOMERS IN MANITOBA INCLUDED IN SALE PRICE! S3 3 HP TURBO fans are designed to fit on a 18" diameter round aeration transition. The suction end of this fan flares out to 24" in diameter. This allows for a larger diameter wheel which increases tip speed. Fan performance under high static pressure is much better than an inline fan. All S3 aeration fans are equipped with an aluminum wheel assembly for efficient power usage. The fan housing is painted steel for long life and fan controls are "Bin Sense Ready"