STAINLESS STEEL (PART THREADED) VALVE COMPONENT. IT IS SHAPED LIKE A NUT AND PROVIDES A LEAK TIGHT SEAL AND IT COMES IN VARIOUS SIZES. THE INTERIOR OF THE NUT IS SPECIALLY COATED TO CREATE THE SEAL. THE DIFFERENT OPENING DIAMETERS ARE DESIGNED TO SECURE THE FITTING AND TO CREATE A SEAL. AT THE SIDE OF THE NUT ARE TWO SMALL HOLES WHICH ARE USED AS LEAK TEST PORTS.

GIR 1 & 6. THE TEXT TO TARIC CODE 8481 90 00 90. THE HSEN TO HEADING 8481.