The JBX88389 40-meter ST/ST duplex singlemode fiber patch cable represents a critical infrastructure component for modern high-speed data centers, telecommunications facilities, and enterprise networks requiring reliable long-distance optical signal transmission. **Technical Excellence** This cable features a 9/125 micrometer core specification optimized for singlemode operation at telecommunications wavelengths (1310nm and 1550nm). The G.657.A1 glass fiber provides superior bend insensitivity while maintaining attenuation standards of 0.25 dB/km at 1310nm and 0.35 dB/km at 1550nm. With typical insertion loss of just 0.15dB and maximum of 0.35dB, signal degradation is minimized across the 40-meter span, ensuring data integrity for critical applications. **Performance Specifications** The ST/UPC connectors deliver ≥20dB return loss, effectively eliminating signal reflections that compromise performance. Type A to B crossover polarity configuration follows industry standards for duplex patch cord applications. All specifications comply with ANSI/TIA/EIA-455-171-A-2001 attenuation testing standards. **Installation and Safety** The riser-rated (OFNR) jacketing is crucial for commercial building installations, providing flame resistance and smoke control per National Electrical Code requirements. The compact 1.8mm diameter enables efficient cable management in congested infrastructure environments. Custom lengths are available for unique deployment scenarios. **Compliance and Certification** TAA compliance ensures eligibility for government and large enterprise procurement. RoHS/ELV certification (EU Directive 2002/95/EC) demonstrates environmental responsibility and compliance with international regulations. Manufactured with precision in Taiwan, the US, or China, this cable meets rigorous quality standards. **Ideal Applications** Perfect for data center backbone connections, telecommunications equipment interconnection, fiber-to-the-premises installations, and enterprise LAN upgrades. The 40-meter length accommodates moderate-distance runs common in multi-floor buildings and campus networks. **Value and Support** Includes 90-day limited warranty. Free standard shipping on orders exceeding $99. Ships from multiple US locations (Danville CA, Fort Worth TX, Beaufort SC) for expedited delivery.