there are two types of UV tubes for bug zappers: Black light & Black Light-Blue glass
GEs website says the difference btwn BL and BLB is that BLB have dark glass which traps visible light producing the maximum amount of UV? this doesnt make much sense to me...having an opaque glass will just trap visible light not generate more UV, right? or not? thx
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Blacklight-blue bulbs are designed with a special deep-blue glass that filters out visible light, producing the maximum amount of ultraviolet light possible. If you're looking for a blacklight that produces the minimum amount of visible light for an especially sensitive area, blacklight-blue bulbs are an ideal choice