This Siemens 20 Amp Surge Protected Circuit Breaker will trip when surge protection is lost to provide safe use. This circuit breaker offers a dual single-pole design and 2 LED indicator lights. By installing a Siemens Circuit Breaker and Surge Protection Device in the load center of the residence, surge protection is provided for all branch circuits. 150 VAC, 40 mm metal oxide varistors 2 green LED indicator lights show when surge protection is provided Circuit breaker and SPD utilize Siemens-built 150-Volt AC, 40 mm, metal oxide varistors (MOV's) Comprised of a highly-effective TVSS integrated with 2 single-pole 20 Amp circuit breakers Notifies of loss of surge protection by tripping Joules: 720 Electrical Product Type: Whole House Surge Protectors Maximum Amperage (amps): 20 Connection type: Breaker Product Weight (lb.): 1 lb Certifications and Listings: 1-UL Listed,ANSI Certified,CSA Listed Product Height (in.): 6.5 Product Width (in.): 6.5 Product Depth (in.): 2.25 in