Custom 77 is a French electric guitar brand founded in 2007 in Lyon by Jérôme and JB, two guitarists and vintage gear enthusiasts who set out to build instruments sold directly to players rather than through traditional retail channels. The instruments are manufactured in Korea and then set up in the company's Lyon workshop. The company also operates a sister brand called Third Eye Guitars, launched in 2011.

The lineup centers on a family of original designs that blend mid-century visual cues with through-neck construction and vintage-style hardware. The first signature model, the Lust For Life, debuted in 2008 and was followed by The Watcher, the T-Sonic, and The Roxy in 2010. Other Original Series models include the Breakdown, Goin' Steady, and London's Burning Mark II.

The brand has built a following in the indie, shoegaze, and alternative rock scenes, with players including Lee Ranaldo of Sonic Youth, members of My Bloody Valentine and Slowdive, Geoff Barrow of Portishead, Jon Spencer Blues Explosion, and Earth associated with the guitars.

Custom 77 has 9 products cataloged on Equipboard, including Solid Body Electric Guitars, Hollowbody Electric Guitars, and Electric Basses. Their gear is featured by 5 artists, with the strongest followings in Rock, Electronic, and Metal. Notable users include Rachel Goswell, Justin Lockey, and Éric Poncet.