Using wire size #2 copper with ground, this 120/240 Volt, two pole replacement breaker is used in a Cutler-Hammer load center. Typical applications, up to 56,000 watts, include furnaces and electrical additions such as a sub-feed panel box. Often this breaker will feed a sub panel to accommodate a GFI breaker that is no longer being manufactured. These are only suggested applications and cannot assure your compliance with all local codes. Please check local electrical codes before starting any electrical project.