Grain bin roof vents are necessary for proper aeration, storage and management of your grain bin.  Brocks tapered style vents are slightly tapered to allow the grain bin vent to slide up slightly farther into your pie shaped roof sheet.....allowing for better ventilation.    90 Degree vents mean the vent opening is parallel with the roof sheets. These vents are often chosen where concerns of snow or moisture may blow into the vents.   The 60 degree vents do not bend down quite as far and allow a little less static pressure.  The mushroom style vent is a round style vent.

The Brock elbow-style roof vent offers 190 square inches (1225 square centimeters) of ventilation opening.

The round mushroom-style vent from Brock provides 180 square inches (1160 square centimeters) of opening. This type of roof vent provides air circulation no matter which way the wind is blowing.

Mushroom Style Dimensions: 16.5” diameter where it attaches to the roof. It stands about 6.375” high. The diameter of the cap is 24”.