MU1-B-34-615-1-A21-B-C is a miniature M-Series circuit breaker designed for demanding applications requiring space-saving features and snap-in front panel mounting. This 2-pole parallel pole construction device operates at a maximum voltage of 65 V DC with a general purpose current rating of 15 A (code 615), featuring an interrupting capacity of 1000 A without backup fuse per UL489A standard. The circuit breaker incorporates a baton actuator style with medium DC time delay (code 34) and push-in stud terminals (code 1), providing balanced circuit protection with compact vertical mounting suitable for telecommunications equipment and single rack unit installations. Its UL489A listing for communications equipment, combined with CSA, VDE, and TÜV certifications, ensures reliable protection in polarity-sensitive applications where space efficiency and aesthetic design flexibility are essential.