{HEAD ~ Spirit level extenders} 9 can be provided in {TAIL ~ different lengths} in the order of say, 12″±4″ or the metric equivalent 
{ HEAD ~ Spirit level extenders } 9 can be provided in { TAIL ~ different lengths } in the order of say , 12″±4″ or the metric equivalent
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH