{HEAD ~ An insert holder} has a cross section with a main positioning side abutting a first primary locating side of {TAIL ~ the insert}, and having a secondary positioning side abutting one of the insert secondary locating sides 
{ HEAD ~ An insert holder } has a cross section with a main positioning side abutting a first primary locating side of { TAIL ~ the insert } , and having a secondary positioning side abutting one of the insert secondary locating sides
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH