Nuts threadedly engage {HEAD ~ the posts} to engage {TAIL ~ the conductive bar} securely to the posts 
to engage
Nuts threadedly engage { HEAD ~ the posts } to engage { TAIL ~ the conductive bar } securely to the posts
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH