The JBX42616 FC/APC to ST/UPC duplex singlemode fiber patch cable represents professional-grade connectivity for mission-critical network environments. This 25-meter cable is specifically engineered to meet the demands of telecommunications, data centers, and enterprise networking applications where signal integrity and reliability are non-negotiable. **Technical Performance:** Utilizing 9/125 singlemode fiber with G.657.A1 glass specifications, this cable delivers exceptional low-loss transmission. Insertion loss measures ≤0.35dB (0.15dB typical), while return loss exceeds ≥20dB, ensuring minimal signal degradation over extended distances. Attenuation performance is rated at 0.25 dB/km at 1310nm or 0.35 dB/km at 1550nm, making it suitable for both traditional and modern optical network frequencies. All performance metrics are validated against ANSI/TIA/EIA-455-171-A-2001 standards. **Connector Architecture:** The FC/APC to ST/UPC configuration provides industry-standard connectivity with angled physical contact (APC) connectors on the FC side and ultra-physical contact (UPC) on the ST side. This Type A to B crossover polarity is the most common configuration for duplex patch cord applications, ensuring compatibility with existing network infrastructure. **Robust Construction:** The bright yellow OFNR (Optical Fiber Non-conductive Riser) jacket provides both visual identification and fire-safety compliance. The 1.8mm outside diameter allows flexible installation through cable trays, conduits, and tight spaces without compromising durability. Plastic accessory components ensure longevity in various environmental conditions. **Compliance & Certification:** Full TAA (Trade Agreements Act) compliance makes this cable suitable for government and federal projects. RoHS and ELV directives compliance (EU directive 2002/95/EC) confirms environmental responsibility and hazardous substance limitations. **Flexibility & Support:** While this product ships in 25-meter length, custom lengths are available for specialized installations. Strategic warehousing in Danville CA, Fort Worth TX, and Beaufort SC ensures rapid fulfillment. Orders exceeding $99 qualify for free standard shipping. The included 90-day limited warranty provides peace of mind for your investment. **Application Scenarios:** Ideal for connecting FC/APC terminations to ST/UPC-equipped network devices in telecommunications closets, data centers, campus backbones, and enterprise networks requiring duplex signal transmission. The low attenuation and high return loss make this cable suitable for bandwidth-intensive applications.