Further, {HEAD ~ each} of the ink filling holes is sealed by combining {TAIL ~ a first cylindrical element}, which is formed on the inner cover encircling the opening, and a second cylindrical element formed on the outer cover to be engaged with the first cylindrical element 
is sealed by combining
Further , { HEAD ~ each } of the ink filling holes is sealed by combining { TAIL ~ a first cylindrical element } , which is formed on the inner cover encircling the opening , and a second cylindrical element formed on the outer cover to be engaged with the first cylindrical element
OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH