Maruszczyk Instruments is a custom bass and electric guitar builder founded by Adrian Kuban-Maruszczyk, a musician-turned-luthier with decades of playing and touring experience. The brand operates under the Public Peace umbrella, which serves as the company's showroom and distribution arm, with instruments hand-built in a small European workshop. Maruszczyk's pitch centers on delivering boutique-level craftsmanship and deep customization — tonewoods, pickups, electronics, finishes, and hardware — at prices well below most handmade competitors.

The bass catalog is the brand's best-known output and includes the Jake (in C, Basement, 55, and TB variants), the Frog and Frog Headless, the Jazzus, the Mopped B, and signature models such as the Pi-Bass for Wojtek Pilichowski and a Bruno Tauzin signature. Each model is available in fretted or fretless configurations and across 4-, 5-, and 6-string builds. On the guitar side, Maruszczyk builds the Elwood family (C, Absolution, L, Europe, X), along with the Hellwood, Mr. Tee, Paddock, Phoenix, Sputnik, and Svoboda.

The company has developed a following on forums like TalkBass and Basschat, where players frequently cite the fit, finish, and per-build configurability as the brand's draw. Maruszczyk basses are stocked by specialist European retailers including Bass Direct, Bass Freaks, and MelacantoMelasuono, and the company is closely associated with sister brands Mensinger Guitars and Hevos amplification under the Public Peace roof.

Maruszczyk has 5 products cataloged on Equipboard, including Electric Basses. Their gear is featured by 1 artist, with the strongest followings in Electronic, Funk / Soul, and Jazz. Notable users include Wojtek Pilichowski.