A system having pressurized fluid flowing therethrough comprising: a component having a first conduit, wherein the component discharges pressurized fluid through the first conduit, wherein the first conduit comprises a first conduit threaded end having a first length (Li); a second conduit comprising a second conduit threaded end having a second length (L 2); and a coupling nut constructed and arranged to join the first conduit and the second conduit, the coupling nut comprising: a first end; a second end; an opening extending between the first end and the second end, the opening having an interior surface; a first coupling nut thread extending along the interior surface at the first end and constructed and arranged to receive the first conduit threaded end; a second coupling nut thread extending along the interior surface at the second end and constructed and arranged to receive the second conduit threaded end; and a non-threaded central portion extending between the first coupling nut thread and the second coupling nut thread, the non-threaded central portion having a third length (L 5), wherein the third length (L 5) of the non-threaded central portion is less than the sum of the first length (L 1) of the first conduit threaded end and the second length (L 2) of the second conduit threaded end; wherein the third length (L 5) is greater than the first length (L 1); and wherein the third length (L 5) is greater than the second length (L 2); characterised in that if the first conduit is inserted into the coupling nut too far, the first conduit threaded end will become positioned within the non-threaded central portion of the coupling nut so that the first conduit will rotate freely with respect to the coupling nut; and/or if the second conduit is inserted into the coupling nut too far, the second conduit threaded end will become positioned within the non-threaded central portion of the coupling nut so that the second conduit will rotate freely with respect to the coupling nut. a second conduit comprising a second conduit threaded end having a second length (L 2); and a coupling nut constructed and arranged to join the first conduit and the second conduit, the coupling nut comprising: a first end; a second end; an opening extending between the first end and the second end, the opening having an interior surface; a first coupling nut thread extending along the interior surface at the first end and constructed and arranged to receive the first conduit threaded end; a second coupling nut thread extending along the interior surface at the second end and constructed and arranged to receive the second conduit threaded end; and a non-threaded central portion extending between the first coupling nut thread and the second coupling nut thread, the non-threaded central portion having a third length (L 5), wherein the third length (L 5) of the non-threaded central portion is less than the sum of the first length (L 1) of the first conduit threaded end and the second length (L 2) of the second conduit threaded end; a first end; a second end; an opening extending between the first end and the second end, the opening having an interior surface; a first coupling nut thread extending along the interior surface at the first end and constructed and arranged to receive the first conduit threaded end; a second coupling nut thread extending along the interior surface at the second end and constructed and arranged to receive the second conduit threaded end; and a non-threaded central portion extending between the first coupling nut thread and the second coupling nut thread, the non-threaded central portion having a third length (L 5), wherein the third length (L 5) of the non-threaded central portion is less than the sum of the first length (L 1) of the first conduit threaded end and the second length (L 2) of the second conduit threaded end; wherein the third length (L 5) is greater than the first length (L 1); and wherein the third length (L 5) is greater than the second length (L 2); characterised in that if the first conduit is inserted into the coupling nut too far, the first conduit threaded end will become positioned within the non-threaded central portion of the coupling nut so that the first conduit will rotate freely with respect to the coupling nut; and/or if the second conduit is inserted into the coupling nut too far, the second conduit threaded end will become positioned within the non-threaded central portion of the coupling nut so that the second conduit will rotate freely with respect to the coupling nut.