Amazon Kindle Paperwhite (6th Generation) 2GB, Wi-Fi, 6in - Black for sale online | eBay
How to see your serial number, firmware version, and storage on Kindle
How to Update Kindle Paperwhite Firmware
Amazon Kindle Paperwhite (2015) review: The design remains the same, but the screen is sharper - CNET
2 kindle paperwhites same model in the same UK house updated to latest firmware now have different User Interfaces. One kindle won't activate new UI even after system reset and logging back
How to see your serial number, firmware version, and storage on Kindle
Which Kindle do I have? A quick guide to identifying Amazon's e-readers