These lights have been ordered for the X-ray image of a developer friend (vet). The bulbs work exactly as you would expect from light bulbs and fit for purpose (according to the statement of the vet) radiographic developer properly. Since the normal light bulbs are by now no longer get or only extremely rare, I was asked the same with a large supply order (25 bulbs). The life expectancy of normal life for light bulbs and lighting fixtures are (otherwise be expected as a Philips product) and processed properly. All in all: TOP!