1.  Generation 4 digital I/O, introduced by Opto 22 in 1989, provides increased density over older modules, while maintaining single-channel flexibility.

2.  Optical isolation on these modules provides 4,000 volts of transient (4000 V for 1 ms) protection for sensitive control electronics from industrial field signals

3.  SNAP Quadrature Input Module

4.  SNAP Digital Output Modules

5.  SNAP High-Density Digital I/O Modules