Through terminal block, 870 Series, operating tool This through terminal block (item number 870-904) is designed for easy and secure connections. Strip lengths must be between 6 and 7 mm when connecting conductors to this through terminal block. Our mini rail-mount terminal blocks are the perfect choice when space is limited. A large selection of mounting and actuation variants means you can find a suitable mini terminal block for every purpose. This also means you can adapt the terminal blocks to your unique requirements. Featuring conductor terminals along with CAGE CLAMP®, this connector delivers reliable performance. Our celebrated universal connection known as CAGE CLAMP® is the industry standard when it comes to connection technology and electrical interconnections. This through terminal block is suitable for conductor cross sections ranging from 0.08 mm² to 2.5 mm². This mini rail-mount terminal block is operated with an operating tool.