SM331 EXTEND MODULE (6ES73317NF000AB0) SIMATIC S7-300, ANALOG INPUT SM 331, OPTICALLY ISOLATED, 8 AE; +/-5/10V, 1-5 V, +/-20MA, 0/4 TO 20MA, 16 BIT (55 MS), 1 COMMON POINT(50 V COM.), 1 X 40 PIN AND SIMATIC S7-300,FRONT CONNECTOR (6ES73921AM000AA0) 392 WITH SCREW CONTACTS, 40-PIN