Variants
Although not specifically considered "Variants" there are a number of other models that share the AN/PVS-4 lineage and often use interchangeable components, including the image intensifier tube.
The addition of a "A" after the model, e.g., AN/PVS-4A, signifies a third-generation image intensifier tube and may be designated either after upgrade or at original manufacture. "A" variants typically use "AA" batteries.
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