Particularly geared towards health and safety-conscious food service businesses and properties where insects are an issue, our great selection of fly killer fittings and tubes are totally dependable. Black-light bulbs are not to be confused with black-light blue (BLB) ones. While they’re named similarly, and both give off UVA light, they have very different uses. Black-light bulbs (often referred to as BL368 or BL350) are the ones you will see used in bug zappers in shops and kitchens, as the bugs are attracted to the UV light. These bulbs commonly come in opaque white tubes – either straight or turned into more compact shapes. They emit a mixture of ultraviolet and visible light and will appear to glow a luminous blue colour when in operation. Get a long-lasting solution to your fly problems today with LightBulbs Direct.