SIEMENS 6DD1688-1AA0 Description Description SIEMENS SIMADYN D INTERFACE SUBMODULE SS1 20MA (TTY) Related products SIEMENS 1FK6032-6AK71-1TG0 SIEMENS 1FK7022-5AK71-1AG0 SIEMENS 1FN1910-0AA20-1AA0 SIEMENS 1FT5066-1AF71-4AA0 SIEMENS 1FK7044-7AF71-1EG0 SIEMENS 1FK6042-6AF71-1TH0