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