HD Series Also called the following depending on Amperage, HD 030, HD060, HD 100 and HD 150. The Interrupting Capacity of this type of Circuit Breaker is 18,000 @ 480 Volt and will fit in all Square D I-Line Panelboards old and new. This Circuit Breaker is Plug-in manufactured from 15 to 150 amp including half sizes 25,35 and 45 Amp