National Library Service for the Blind and Print Disabled
The National Library Service for the Blind and Print Disabled (NLS) is a free library program of braille and audio materials such as books and magazines circulated to eligible borrowers in the United States and American citizens living abroad by postage-free mail and online download. The program is sponsored by the Library of Congress.
Source: Wikipedia — National Library Service for the Blind and Print Disabled (CC BY-SA 4.0)