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Amazon on Wednesday unveiled an updated version of its high-end Kindle Oasis e-reader that adds the ability to adjust the color temperature of the screen. It's a first for a Kindle e-reader.

Color temperature correlates to the look and feel of light produced. Warmer temperatures exhibit an orange or yellowish tint and are generally a bit easier on the eyes while cooler temperatures have a bluish tint, giving off a crisp and invigorating ambience.

Recent research suggests that blue light from electronic devices may affect sleep and could even increase your risk of blindness.

The new Oasis also has an adaptive front light that can automatically adjust screen brightness based on ambient lighting conditions. Like its predecessor, it features an IPX8 rating meaning it can withstand being submerged in up to two meters of fresh water for an hour and utilizes a seven inch, 300 PPI Paperwhite display.

Amazon's new Kindle Oasis is available to pre-order as of writing. Offered in your choice of black or gold, it goes for $249.99 with 8GB of onboard storage or $279.99 with 32GB of space, both with Amazon's "special offers" advertising (you can get it ad-free for $269.99 or $299.99). Look for it to ship on July 24, 2019.