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Use the first 4 digits to find your model bellow
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The next couple of images illustrate this.
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On early models (Kindle 1, Kindle 2 & DX), it was also physically visible on the device itself, on the back at the bottom (on the Kindle 1, it was under the back cover), and also on the packaging the devices were shipped in. If you’ve been switched to the new layout, this is now shown in the Your Devices tab of the Manage Your Content and Devices page of your Amazon account. If you don’t have the device on hand at the time, it is also shown on the Manage Your Kindle page of your Amazon account (in the Manage Your Devices section). On that page, you should find either an entry or a menu called Device Info, which will give you the serial number The easiest way to find it is in the Settings page/menu on your Kindle
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This is article about how to find your Kindle model from the serial number of your device.
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