***spare part*** SIPLUS S7-1200 SM 1221 16DI, based on 6ES7221-1BH30-0XB0 with conformal coating, 0…+55 °C, 16 DI, 24 V DC, sink/source Just like the CPU, the digital input modules are also protected against extreme ambient conditions. Due to the 100% conformal coating they can withstand biologically, chemically and physically active substances, condensation, frost, and corrosive gases. Regardless of the conditions, your digital signals are reliably recorded.