... ,big air volume, no distortion, no broken2. new design fan house, light weight, elegant appearance, easy to install3. Round protection grill ... ≤7075038012201220420DJF(d)-1380125041014003500056≤70110038013801380420DJF(d)-1530140030014004400060≤70150038015301530420 DJF-D cow house exhaust fan