Through terminal block, 280 Series, operating tool This through terminal block (item number 280-651) is designed to connect conductors quickly and easily. Conductors should only be connected to this through terminal block if their strip length is between 8 and 9 mm . 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. This product features conductor terminals and utilizes CAGE CLAMP®. Our highly-rated and maintenance-free CAGE CLAMP® connection makes it easy to connect all types of conductors without having to prepare the conductor. For example, you don't need to crimp 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.