Comparison : Item # PDA1002, DIN Rail Mounting Kit for Two Expansion Modules
Item # PDA1004, 4-Relay Expansion Module
Item # PDA1011, Dual 4-20 mA Output Module
Item # PDA1044, 4 Digital Inputs & 4 Digital Outputs Module
Item # PDA7485-I, RS-232 to RS-422/485 Isolated Converter