Graham Partners has completed an investment in Rhythmlink International, according to a news release.

Rhythmlink, based in Columbia, S.C., is a designer and manufacturer of disposable neurodiagnostic devices and consumables. Founded in 2002, the company’s devices support intraoperative neuromonitoring, electroencephalography, evoked potentials, polysomnography, long-term monitoring epilepsy and critical care units.

Graham Partners, based in Newtown Square, Pa., is a private equity firm that specializes in industrial technology and advanced manufacturing businesses. Founded in 1988, the firm pursues control or minority capital investments and typically targets companies with EBITDA up to $50 million

Terms of the investment were not disclosed.