How long do Bowens bulbs/fuses normally last?

Are you referring to the halogen model light or the flash tubes? The model light is not made by Bowens, it's just a halogen bulb from GE, Osram, etc. Assume the average lifespan of those bulbs, depending on how they are treated (mechanical agitation while burning, full or reduced burning...).

The flash tube will be good for 50K or more pops, also depending on the power (setting) of each pop.

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cheers, Peter
Germany