The Owl Perimeter Defense Solution OPDS-100D is a hardware-based data diode designed for industrial control system deployments. The device features a compact form factor that is DIN rail mountable, making it suitable for installation in plants and other industrial facilities. The OPDS-100D provides one-way data transfer capabilities to protect industrial control networks from external threats while allowing necessary data to flow out of protected environments. This hardware-enforced unidirectional data flow prevents unauthorized access and cyber attacks from reaching critical operational technology infrastructure. The product was specifically engineered for industrial control deployments where space constraints and environmental conditions require ruggedized, compact solutions. The DIN rail mounting capability allows for easy integration into existing industrial control panels and cabinets. Note: Production of the OPDS-100D has been indefinitely halted due to supply chain shortages and this product is no longer available for sale. The manufacturer recommends the OPDS-1000 as an alternative with similar operational characteristics supporting additional use cases.