Amazon officially announced its eBook and audiobook subscription service Kindle Unlimited on Friday after an accidental leak revealed the details of the service less than 24 hours earlier. Subscribers will have access to over 600,000 eBooks and thousands of Audible audiobooks on Kindles as well as iOS, Android and other devices for $9.99 a month, BGR reports.

Eligible books will feature the Kindle Unlimited logo and a “Read for Free” button. On top of the thousands of free audiobooks available to subscribers, anyone who signs up for Kindle Unlimited will be given a complimentary three-month membership to Amazon’s Audible service as well, which offers over 150,000 audiobooks to members.

“With Kindle Unlimited, you won’t have to think twice before you try a new author or genre—you can just start reading and listening,” said Russ Grandinetti, Senior Vice President, Kindle. “In addition to offering over 600,000 eBooks, Kindle Unlimited is also by far the most cost-effective way to enjoy audiobooks and eBooks together. With thousands of Whispersync for Voice-enabled audiobooks to choose from, you can easily switch between reading and listening to a book, allowing the story to continue even when your eyes are busy. We hope you take advantage of the 30-day free trial and try it for yourself.”