The DS2413 is a 1-port switch (4mA) & input (PIO) module.
Unfortunately it is no longer manufactured. As a replacement, we recommend the type DS2413.
Alternatively, you can set each of the eight channels as "Digital Output" or "Digital Input". Additionally you can "invert the status" (see DS2413). For testing purposes, you have the ability to switch the output "ON" and "OFF".