Referring to FIGS 1, 2, 4 and 5 again, {HEAD ~ the wedge block} 3 comprises {TAIL ~ a wedged base} 31, two serrated portions 32 bilaterally disposed near the top, a center opening 33, and two dovetail projections 34 bilaterally projecting into the center opening 33 
comprises
Referring to FIGS 1 , 2 , 4 and 5 again , { HEAD ~ the wedge block } 3 comprises { TAIL ~ a wedged base } 31 , two serrated portions 32 bilaterally disposed near the top , a center opening 33 , and two dovetail projections 34 bilaterally projecting into the center opening 33
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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