... boards, the BD boards can be analog input, output,LCD: Monochrome LCD, yellow-green backlight,PLC: 8 points input, 8 points transistor/relay/mixed output ... C10DI/8DO, 4channels transistor/4 channels relay output, 3.7 inch blue LCDXMP3-18R-C10DI/8DO, relay output, 3.7 inch blue touch ... Can expand 2 BD cardsXP3-16RT-E8DI/8DO, 4 relay output, 4 transistor output, 3.7 inch blue LCD; support RS485, 2CH ...