{HEAD ~ The block back legs} may extend in a plane parallel to the block front surface or extend forwardly toward {TAIL ~ the blocks front surface} 
extend forwardly toward
{ HEAD ~ The block back legs } may extend in a plane parallel to the block front surface or extend forwardly toward { TAIL ~ the blocks front surface }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL