{HEAD ~ A motor} has speed and airflow parameters and {TAIL ~ a built in constant airflow regulator} 
has
{ HEAD ~ A motor } has speed and airflow parameters and { TAIL ~ a built in constant airflow regulator }
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL