XFN-400 is a water-blocking compound specifically designed for filling optical fiber buffer loose tubes at high line speeds. 

XFN-400 is silica free, soft, non-sticky hydrophobic compound, flexible down to –50°C, non-draining at 80°C and thixotropic for controlled filling at ambient temperature. Polygel XFN-400 is non nutritive to fungus, exhibits low hydrogen generation, zero oil separation with excellent resistance to oxidation for long-term stability.

Product Name

Filling Compound For Optical Fiber Cable

POLYGEL XFN-400 is compatible with most cable grade polymers. Tests on typical acrylate coated optical fiber shows no reaction but it is recommended that compatibility tests are made with all materials likely to come into contact with the gel.


POLYGEL XFN-400 is suitable for cold pumping and processing enabling cable filling without voids created by compound shrinkage. A line-synchronized gel metering system is available comprising of a drum pump, de-aeration, filtration unit and a metering control unit for stable dosing of the gel.