Amazon Kindle Gen 10(2019) 8GB with Built in Front Light - Free 8000 ebooks

Adjustable front light lets you read comfortably for hours—indoors and outdoors, day and night.
Purpose-built for reading, with a 167 ppi glare-free display that reads like real paper, even in direct sunlight.
Read distraction-free. Highlight passages, look up definitions, translate words, and adjust text size—without ever leaving the page.
Enjoy more books with Audible. Pair with Bluetooth audio devices to switch seamlessly between reading and listening.

Difference between the USA and Japan versions is just the warranty, either from Amazon USA or Amazon Japan.
Warranty of 6 Months by Amazon

Display
Amazon's 6” display with built-in light, 167ppi, optimized font technology, 16-level gray scale.
Size
6.3” x 4.5” x 0.34” ( 160 x 113 x 8.7 mm).
Weight
6.1 oz (174 g). Actual size and weight may vary by configuration and manufacturing process.

System Requirements
None; fully wireless and doesn't require a computer to download content.
On-Device Storage
8GB; holds thousands of books.
Cloud Storage
Free cloud storage for all Amazon content.
Battery Life
A single charge lasts up to 4 weeks, based on a half hour of reading per day with wireless off and the light setting at 13. Battery life will vary based on usage. Audible audiobook streaming over Bluetooth will reduce battery life.

Charge Time
Fully charges in approx 4 hours

Wi-Fi Connectivity
Supports public/private Wi-Fi networks or hotspots that use 802.11b/g/n standards.

Content Formats Supported
Kindle Format 8 (AZW3), Kindle (AZW), TXT, PDF, unprotected MOBI, PRC natively; HTML DOC, DOCX, JPEG, GIF, PNG, PMP through conversion; Audible audio format (AAX).