The JBX11430 SC/UPC to ST/UPC singlemode duplex fiber coupler represents a critical component for modern optical fiber networks. This precision adapter bridges SC/UPC and ST/UPC connector types, enabling flexible fiber cable configurations across diverse telecommunications and data center applications. **Key Features:** This one-piece fiber coupler delivers exceptional reliability through its solid plastic construction, engineered to withstand repeated connections and environmental variations. The blue finish serves both aesthetic and identification purposes in complex network installations. With support for dual singlemode fibers, the JBX11430 maintains signal integrity across extended network distances. **Technical Specifications:** Dimensions measure 4.0 x 1.0 x 0.5 inches, providing compact integration into standard fiber management systems. The adapter accommodates two singlemode fibers simultaneously, supporting duplex communications. Manufactured in Vietnam and China using quality-controlled processes, each unit undergoes rigorous testing to ensure performance specifications. **Applications & Use Cases:** This fiber coupler serves telecommunications professionals, network integrators, and data center technicians requiring SC/ST interconnection capability. Ideal applications include LAN backbone connections, telecommunications closet patching, and equipment interconnection where singlemode fiber performance is essential. The coupler maintains excellent insertion loss characteristics critical for long-distance fiber runs. **Compliance & Warranty:** Fully compliant with EU directive 2002/95/EC RoHS standards, this optical coupler meets international environmental regulations. Ships from distribution centers in Danville, CA and Beaufort, SC for rapid delivery. Every purchase includes a comprehensive 90-day limited warranty protecting your investment. **Why Choose This Fiber Coupler:** Professional-grade construction ensures stable optical performance in mission-critical networks. The universal SC/UPC to ST/UPC compatibility eliminates the need for multiple adapter types. Free standard shipping on orders exceeding $99 provides exceptional value for bulk purchases and system upgrades.