As with all UV2 dubbings, these have a mix of primary colors that have been enhanced with UV Florescence and UV Reflectance dyes.
The dubbing is then blend these in with other fibers to achieve the over all base color while still giving it all the multi color property's of UV2.
Each dubbing will kick out a host of color spectrums.
Check them out in direct sunlight.
It is best to always use a pearl or silver Mylar under base or even basic white thread which will bounce any light back out of the pattern at a different wave length.