The folding 8-track, or Mini-8, was a response to the compact cassette, which by the late 1960s had started to move in on the 8-track's market for pre-recorded music. Lear Jet, which invented the 8-track, came up with an unlikely solution: a cartridge that could be folded into a package similar in size to the cassette. When unfolded, the cartridge fit in a standard 8-track player. Unfortunately, the reduced size meant it could hold only 30 minutes of music. It also didn't address the other advantages of cassettes, which could be rewound, were easy to record, and didn't interrupt the music four times to switch tracks. The Mini-8 failed quickly.