Through terminal block, 280 Series, operating tool Our through terminal block (item number 280-101) ensures effortless electrical installations. Strip lengths must be between 8 and 9 mm when connecting conductors to this through terminal block. Whether for use in industry or building installations, our rail-mount through terminal blocks allow you to quickly and securely connect electrical conductors. They’re perfect for either classic through-wiring or distributing potential, depending on the variant. Featuring conductor terminals along with CAGE CLAMP®, this product delivers reliable performance. Our CAGE CLAMP® connection offers a safe 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. This through rail-mount terminal block is operated with an operating tool.