The presence of the intermediate layer allows the cutting tool to safely and completely cut a spot and remove the cut spot from {HEAD ~ the gel} or {TAIL ~ membrane} without scratching or otherwise damaging the surface, and with at most a temporary depression in the intermediate layer 
The presence of the intermediate layer allows the cutting tool to safely and completely cut a spot and remove the cut spot from { HEAD ~ the gel } or { TAIL ~ membrane } without scratching or otherwise damaging the surface , and with at most a temporary depression in the intermediate layer
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 HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH