What is special name suffix "/BLB"?
This special name encoding reference means: black-light blue. Narrow filtered UV output fluorescent "black-light blue" bulbs which are BLACK (dark purple) color when OFF.
Wide spectrum (unfiltered) UV output fluorescent bulbs are designated /BL "black-light" and are WHITE color when OFF.
references for this page: /BLB, BLACK-LIGHT BLUE, BLACK LIGHT BLUE
reference to this page: /BL