A mottled candle and its method of manufacture are disclosed herein. The two tools are arranged coaxial with each other at different ends of a C-bracket. A flag setting unit sets whether the audio pack is to be completed or not in accordance with the result of comparison by the time zone comparing unit. The first and second brain regions may be the same brain regions or different brain regions. Each of the removable optical modules is optically configured to excite the species and capture fluorescent light emitted by the species at different wavelengths. The fiber-reinforced body member of the coupling not only adds hoop strength to the coupling nut, but prevents the metal coupling nut from being exposed to corrosive elements such as salt or the like.