Wieland fasis duo feed through din blocks wkfn d1235 32a41a bluegrey wieland 5670451550 wielands grey fasis duo feed through din block wkfn 4 d2235 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 a 32a