Marty McFly Jr and Marlene with Video Glasses.
Video glasses were an input device, used in 2015, to view television programs without a large screen. Marty McFly Jr. wore a pair of JVC video glasses while eating dinner with his family, and complained that the glasses only allowed him to watch two channels. His sister, Marlene McFly, had a different set of glasses that apparently allowed her to talk on the telephone. The McFlys only had one phone line, so she had to interrupt her conversation when Needles called.