Carlo Gavazzi GMB63 miniature circuit breaker is for 240VAC or 480Y/277V applications where supplementary or branch circuit protection is required. The GMB63 is available as a 1, 2 or 3 pole circuit breaker with an amperage rating of up to 50A and is UL489 rated for branch circuit protection. The GMB63 utilizes a bimetallic element for small overloads and a magnetic element for short circuit protection.