American Fibertek 4 Channels Bi-Directional Module Transmitter, Signal Source

4 Channels Bi-Directional, Form-C (Normally Open or Normally Closed) Dry Contact Closure Latching Relays reduce power requirement User-Selectable feature maintains Contact Status through Power-Cycle and Loss-of-Optical-Power User Control to Reset all Contact Status Diagnostics: Power, Optical Presence and Channel Indicators