interior edge of the end cap 77 fig1 a depicts the embodiment with a plurality of tabs as the hooking crest 85 an example of a block 10 that includes one or more hook receiving devices 83 is depicted in fig1 b wherein a series of ridges are present within the interior of the block 10 in yet another embodiment a partial block may be formed by cutting a block 10 into two separate sections trimming one of the sections forming a slot in the trimmed section and nesting the trimmed section into the other section fig1 c and 14d depict one embodiment of a nested partial block as depicted in fig1 c a block 10 is cut into two sections 11 and 13 one of the sections is then trimmed to allow for the nesting of the trimmed section 11 within the other section that is visible when placed in a wall the visible section 13 fig1 d depicts the trimmed section 11 being nested within the visible section 13 generally the majority of the trimmed section 11 will be trimmed and nested completely within the visible section 13 with the exception in some embodiments of the back panel of the trimmed section 11 which may rest outside the back panel of the visible section after nesting a slot 15 may be cut in the back of the bottom panel 14 of the.