For example, if thinner face coatings are desired, then spacers 208 and 211 can be relatively thinner whereas {TAIL ~ relatively thicker spacers} result in {HEAD ~ relatively thicker face coatings} 
For example , if thinner face coatings are desired , then spacers 208 and 211 can be relatively thinner whereas { TAIL ~ relatively thicker spacers } result in { HEAD ~ relatively thicker face coatings }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD