Marathon Special Products has been an industry leader for supplying power blocks in North America since 1955. We’ve achieved this by providing one of the broadest line offerings with various sizes, terminal styles, electrical ratings and features. Our power block offerings are sure to meet your needs. MSP’s power blocks are either UL recognized or listed. Most have either CSA certification or cUR recognition for Canadian customers, as well as compliance to CE (Component IEC 60947-7-1). Recognized power blocks comply to UL 1059 and CSA C22.2 No. 158. All of our power blocks meet the 600V spacing requirements for application classes B & C and some Class A (135s). Listed power blocks comply to UL 1953. These are all rated 600V and are intended to be used on the load side of service equipment in accordance with the National Electrical Code, NFPA 70. These blocks are used for splicing conductors in metallic wireways, auxiliary gutters, junction boxes, termination boxes and control panels in order to distribute power to separate loads. Listed power blocks additionally provide feeder circuit terminal spacing requirements of UL508A.