Profoto 331523 D1 500/1000 Flashtube (Black) Replacement for D1 500/1000 flashtube. Even though flash tubes are designed to last tens of thousands of flashes, sometimes one is broken to due to rough conditions or other hazards. Here is the replacement.1000Ws Even though flash tubes are designed to last tens of thousands of flashes, sometimes one is broken to due to rough conditions or other hazards. Here is the replacement.1000Ws