Through terminal block, 280 Series, operating tool Our through terminal block (item number 280-835) ensures effortless electrical installations. Strip lengths must be between 8 and 9 mm when connecting conductors to this through terminal block. Whether in industrial or building applications, our rail-mount through terminal blocks are the perfect solution to quickly and securely connect electrical conductors. Depending on the version, you can use them for either typical through-wiring or potential distribution. Featuring conductor terminals along with CAGE CLAMP®, this connector delivers reliable performance. Our CAGE CLAMP® connection offers a convenient and maintenance-free way to connect all types of conductors. You do not need to prepare the conductor in any way, such as crimping ferrules. This through terminal block is suitable for conductor cross sections ranging from 0.08 mm² to 2.5 mm². An operating tool is used to operate this through rail-mount terminal block.