Color of the outer sheath of the pigtail

Single-mode pigtails have a yellow outer sheath, while multimode pigtails are typically orange or aqua depending on the multimode type.

Standard Color Coding

• Single-mode pigtails: Yellow outer sheath, designed for long-distance transmission with wavelengths of 1310nm or 1550nm, supporting distances up to 10km or 40km .
• Multimode pigtails:
  • OM1/OM2: Orange outer sheath, wavelength 850nm, suitable for short-distance connections up to 500m .
  • OM3: Aqua outer sheath, optimized for higher-speed short-distance connections, typically used in data centers .

Practical Notes

The outer sheath color helps technicians quickly identify the fiber type and match it with the appropriate optical modules. Using the wrong type can lead to signal loss or incompatibility. In high-density or multi-fiber setups, pigtails may also follow TIA-598-C color standards for individual fibers inside a bundle, but the outer sheath color remains the primary visual indicator for single-mode versus multimode . In summary, yellow indicates single-mode, orange indicates standard multimode (OM1/OM2), and aqua indicates high-speed multimode (OM3/OM4), providing a clear visual guide for installation and maintenance.