Video/Audio: 4K Ultra HD, Dolby Vision, HDR10+, Dolby Atmos. The Fire TV Stick 4K Plus is Amazon's updated, more capable 4K streaming stick, essentially the standard 4K model with key upgrades like a faster processor, Wi-Fi 6 for smoother streaming, 2GB RAM (double the base 4K Select), and support for Dolby Vision/Atmos, all running on the familiar Android-based Fire OS, differentiating it from the newer, more locked-down "Vega OS" (Fire TV Stick 4K Select) that lacks sideloading and Dolby Vision.
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