Features: Telecom grade single mode 9/125 fiber loopback ensures stable performances in high capacity data transmission with low signal loss for telecom networks. Precise engineered with low loss 9/125 single mode fiber for consistent signal integrity across environmental variation. Pocket sized loopback design enables seamlessly fiber channel verification while maintaining 0.2dB typical insertion loss for uninterrupted networking diagnostics. Ideal for networking administrators, telecom engineers, and data center technicians requiring stable short distance fiber optical connection solution. Optimized for backbones networking testing, fiber optical maintenance, and signal quality verification in enterprise grade infrastructure. Specifications: Size: 22x67x10mm. Weight: 30g. Return loss: ≥50dB. Usage function: used to test signal backhaul in a system or networking systems. Operating temperature: -40°C - 80°C. Package Includes: 3pcs Fiber Loopback note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you donot mind befores you order. 2.Due to the differences between different monitors, the picture may not reflect the actual color. Thanks for your understandings.