Tool 11 has bubble level 12 mounted in {HEAD ~ one end} of the tool 11 and {TAIL ~ a thumb screw} 8 mounted in the opposite end 
Tool 11 has bubble level 12 mounted in { HEAD ~ one end } of the tool 11 and { TAIL ~ a thumb screw } 8 mounted in the opposite end
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH