This means the first part of the housing terminates with one front side of the cartridge or the front side projects somewhat over {HEAD ~ the first part} of {TAIL ~ the housing} 
of
This means the first part of the housing terminates with one front side of the cartridge or the front side projects somewhat over { HEAD ~ the first part } of { TAIL ~ the housing }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL