The side walls 47, 38 are parallel with each other and have {TAIL ~ a pair} of {HEAD ~ holes} 49 formed in them to allow a bolt 45 to pass through them 
The side walls 47 , 38 are parallel with each other and have { TAIL ~ a pair } of { HEAD ~ holes } 49 formed in them to allow a bolt 45 to pass through them
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH