The presence of the intermediate layer also allows the use of a cutting tool terminating in a cylinder that has a blunt cutting edge, in addition to tools terminating in {HEAD ~ cylinders} that have {TAIL ~ sharp cutting edges} 
have
The presence of the intermediate layer also allows the use of a cutting tool terminating in a cylinder that has a blunt cutting edge , in addition to tools terminating in { HEAD ~ cylinders } that have { TAIL ~ sharp cutting edges }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL