Through terminal block, 281 Series, gray Our through terminal block (item number 281-652) is the ideal way to connect conductors quickly and securely. Strip lengths must be between 9 and 10 mm when connecting conductors to this through terminal block. Whether for industrial or building applications, you can use our through terminal blocks to connect electrical conductors quickly and safely. We offer variants for both classic through-wiring and potential distribution. This product incorporates conductor terminals and utilizes CAGE CLAMP®. Our trusted universal connection known as CAGE CLAMP® is the industry standard for connection technology and electrical interconnections. Depending on the conductor type, this through terminal block is suitable for conductor cross sections ranging from 0.08 mm² to 4 mm². This through rail-mount terminal block is operated with an operating tool.