The JBX42490 8-meter ST/APC to ST/UPC duplex singlemode fiber patch cable represents a professional-grade solution for telecommunications, data centers, and enterprise network environments requiring reliable, high-performance optical signal transmission. **Product Specifications:** This duplex configuration cable features two individual 9/125 singlemode fiber strands, each precisely terminated with ST connectors. The APC (Angled Physical Contact) connector on one end interfaces with an ST/UPC (Ultra Physical Contact) connector on the opposite end, creating a Type A to B crossover configuration—the most common polarity standard for duplex patch cord applications. The G.657.A1 glass fiber specification provides enhanced bend-loss performance without compromising signal quality. **Performance Characteristics:** With insertion loss specifications of ≤0.35dB and typical attenuation of 0.15dB, this cable delivers exceptional signal quality. The return loss rating of ≥20dB ensures minimal reflective losses, critical for maintaining signal integrity in high-bandwidth applications. Attenuation measurements comply with industry standards: 0.25 dB/km at 1310nm and 0.35 dB/km at 1550nm wavelengths. **Physical Design:** The bright yellow OFNR (Optical Fiber Nonconductive Riser-rated) jacket provides both visual identification and flame-retardant safety compliance. With a compact 1.8mm outside diameter, this cable navigates easily through cable management systems, conduit, and patch panels without excessive space requirements or installation strain. **Regulatory Compliance:** This product meets all TAA (Trade Agreements Act) requirements for federal procurement, includes RoHS/ELV compliance per EU directive 2002/95/EC, and carries a 90-day limited warranty. Manufacturing sources include Taiwan, United States, and China facilities, ensuring reliable supply chain and consistent quality. **Applications & Use Cases:** Ideal for telecommunications networks, financial institutions, healthcare facilities, government agencies, and enterprise data centers. The duplex configuration supports full-duplex communication over single fiber runs, reducing installation costs while maintaining redundancy and performance standards. **Availability & Support:** Available for immediate shipment from multiple U.S. distribution centers (Danville CA, Fort Worth TX, Beaufort SC). Custom length options accommodate specialized installation requirements. Free standard shipping applies to orders exceeding $99, making bulk deployment economically efficient.