Further, {HEAD ~ serrated metallic reinforcing edges} may be mounted to free ends of {TAIL ~ the shield} to enhance their being directed interiorly of a ground surface 
Further , { HEAD ~ serrated metallic reinforcing edges } may be mounted to free ends of { TAIL ~ the shield } to enhance their being directed interiorly of a ground surface
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH