The JBX42666 4-meter FC/APC to LC/UPC duplex singlemode fiber patch cable represents professional-grade connectivity for demanding telecommunications and data center environments. This cable is engineered to deliver reliable signal transmission with superior performance characteristics that exceed industry standards. KEY SPECIFICATIONS: This duplex configuration features two singlemode fiber strands with a precise 9/125 micrometer core diameter, utilizing G.657.A1 bend-insensitive fiber technology. The cable incorporates FC/APC connectors on one end and LC/UPC connectors on the other, configured in the most common Type A to B crossover polarity pattern for seamless integration into existing duplex patch cord systems. PERFORMANCE CHARACTERISTICS: With insertion loss as low as 0.15dB typical (≤0.35dB maximum) and return loss exceeding 20dB, this cable meets stringent ANSI/TIA/EIA-455-171-A-2001 standards. The cable performs optimally across standard telecommunication wavelengths: 1310nm at 0.25dB/km and 1550nm at 0.35dB/km attenuation rates. The 1.8mm outside diameter allows for compact routing in cable trays and tight spaces. COMPLIANCE & QUALITY: TAA-compliant construction ensures eligibility for government procurement. RoHS and ELV directive compliance (EU 2002/95/EC) satisfies environmental and regulatory requirements. The OFNR riser-rated yellow jacket provides fire safety certification for installation in plenum spaces while maintaining visibility in cable management systems. Includes 90-day limited warranty. APPLICATIONS: Ideal for enterprise networks, telecommunications facilities, data center interconnects, and campus fiber backbone installations. The crossover polarity configuration supports standard duplex communication protocols without requiring additional adapters. CUSTOMIZATION: Custom lengths available to suit specific installation requirements. Ships from multiple US locations (Danville CA, Fort Worth TX, Beaufort SC) with free standard shipping on orders exceeding $99.