Hardcore bookworms are obsessed with Kindle Unlimited, a service that unlocks millions of ebooks for just $10 a month. And now, for Black Friday, you can score three months of Kindle Unlimited for just $1. That’s a $29 discount, in case you’re having trouble with the math.

Note: This deal is only available to Amazon Prime members.

A Kindle Unlimited subscription does exactly what you’d expect—it gives you millions of ebooks at no extra charge. You can download up to 20 of these ebooks at a time and read them on any device. Obviously, a Kindle or Fire tablet will work, but you can also use an iPad, a computer, or a smartphone.

Most of the books on Kindle Unlimited are self-published (romance novels, sci-fi adventures, and so on). It’s also worth noting that an Amazon Prime subscription includes some free books, such as the Harry Potter series and a collection of AmazonClassics (which are mainly public domain books).

To redeem this offer, simply visit the Kindle Unlimited signup page and select the “three months for $0.99” offer. Note that Kindle Unlimited will automatically renew at full price after your three months are up (unless you cancel on time).

Source: Amazon via Business Insider