Yuco YC-20-3B Miniature Din Rail Circuit Breaker B Curve 277/480V 50/60Hz 3 Pole (20 Amp) 3rd Party Certifier. UL1077 CSA C22.2. Tested & Certified by TUV Rheinland. Record # 17048084-001. B Curve 3 Pole 20 Amp 277/480V