Air travels through said tube and passes through a plurality of {HEAD ~ holes} along the length of the tube in {TAIL ~ the general direction} of the area where the laser beam strikes the workpiece 
Air travels through said tube and passes through a plurality of { HEAD ~ holes } along the length of the tube in { TAIL ~ the general direction } of the area where the laser beam strikes the workpiece
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH