Wieland fasis multi tier din blocks wkfn 35 blackgreygreen and yellow wieland 5670362550 wielands greenyellow fasis duo multi tier din block wkfn 25 esl35 is a terminal block for mounting onto a ts 35 din rail and has been given an approved atex rating for use in various zones the secure and maintenance free tension spring clamp remains simple to operate via a standard screwdriver which can be held securely in the terminal for optimal handling while connecting wires the block has