{HEAD ~ The components} passing over {TAIL ~ the optical inspection window} may be inspected on the fly, without requiring stoppage of each of the components thereabove 
passing over
{ HEAD ~ The components } passing over { TAIL ~ the optical inspection window } may be inspected on the fly , without requiring stoppage of each of the components thereabove
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH