A fan, with reversible blades, having {HEAD ~ a hub} receiving {TAIL ~ the stem} of the blades and an inner retaining ring, which has outwardly extending projections, supported concentric with the hub 
receiving
A fan , with reversible blades , having { HEAD ~ a hub } receiving { TAIL ~ the stem } of the blades and an inner retaining ring , which has outwardly extending projections , supported concentric with the hub
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH