I have replaced the batteries in 2 duracell 350 flashlights but I can't make them turn on.

The bulbs could be bad, the batteries could be bad, you could have replaced with incompatible batteries or have the wrong orientation. did you realign the compartment to make contact ? often the spot where the batteries go have a wire or metal that connects to another wire or metal when you replace the battery compartment- maybe that metal or wire is not aligned correctly or touching like it should. This was not a question but more of a generalized problem that could have so many solutions. Im not sure more information would have.
good luck
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