Safety rated control relays are required to have positively driven contact elements according to IEC 60947-5-1 Annex L. Positively driven contact elements are a combination of NO auxiliary contacts and NC auxiliary contacts whose construction prevents them from being closed simultaneously. In some industries, such as automotive, the auxiliary contact blocks are required to be permanently attached to meet the requirements of \"unintentional misuse\" as specified in IEC 60292, paragraph 3.12. Tested by SUVA. Siemens Coupling Contactor Relay, DC Operated, 110 VDC Coil, 3NO-1NC, 4 and 8 Pole, Snap-On Mount, Spring Terminal, IP20 Enclosure, -25 to 60 °C, 45 mm W x 73 mm D x 70 mm H