Each tooth of the ring gear has a height and a length, {HEAD ~ the height} extending substantially parallel to {TAIL ~ the axis} of the fastener and the length extending substantially radially from that axis 
Each tooth of the ring gear has a height and a length , { HEAD ~ the height } extending substantially parallel to { TAIL ~ the axis } of the fastener and the length extending substantially radially from that axis
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH