The JBX02149 1000BASE-BX20 SFP optical transceiver module represents a premium solution for extended-reach network connectivity in demanding enterprise environments. Designed as a direct replacement for the Arista SFP-1G-BXD20-53, this module delivers exceptional performance characteristics suitable for complex network architectures requiring long-distance fiber optic transmission. **Technical Specifications & Performance:** Operating at 1 Gigabit per second (1000BASE-BX20), this transceiver utilizes bidirectional transmission over single wavelengths—1550nm for transmission and 1310nm for reception—enabling cost-effective use of single fiber strands. The 20-kilometer reach over standard single-mode fiber (9/125μm core) makes it ideal for metropolitan area networks, campus interconnects, and data center backhaul applications. The module's extended-reach BiDi technology exceeds basic IEEE 802.3ah specifications, offering superior performance for mission-critical applications. **Build Quality & Certification:** Constructed with a robust metal case housing and integrated laser transmitter technology, this transceiver meets international quality standards. The Class 1 Laser certification ensures safety in network environments, while comprehensive compliance certifications—including RoHS/ELV, TUV, UL, and FDA 21CFR 1040.10—guarantee reliability in regulated industries. All components are manufactured in Vietnam and China using quality-controlled processes. **Connector & Installation:** The simplex LC/UPC fiber connector design provides straightforward installation while maintaining optical performance. The compact 5mm × 4mm × 2mm form factor fits seamlessly into standard SFP slots, enabling quick deployment in existing network infrastructure. **Environmental Specifications:** Operating temperature range of 0-70°C (32-158°F) accommodates diverse deployment scenarios from controlled data centers to outdoor network cabinets. The robust design handles temperature fluctuations without performance degradation. **Compatibility & Integration:** Perfect for Arista network switches and compatible with systems supporting SFF-8472 extended-reach BiDi transceivers. Custom brand programming is available for OEM requirements. **Warranty & Support:** Includes 90-day limited warranty with free standard shipping on orders exceeding $99. Ships from Danville, CA or Beaufort, SC locations for rapid delivery nationwide. **Applications:** Ideal for: Data center interconnections, metro Ethernet networks, enterprise campus fiber links, telecommunications infrastructure, and mission-critical network deployments requiring extended-reach single-mode transmission.