The Siemens 6GT2891-4FN10 is a SIMATIC RF, MV plug-in cable, assembled, between ASM 456, RF160C, RF170C, RF18XC and reader, or extension cable for ASM 456, RF160C, RF170C, RF18XC with RF, MV, MOBY PUR, trailing, length 10 m Cable accessory for RF and ASM 456 Modules.