Developed by The Gund Company, PolyPro FR® is a UL Listed flame retardant Polypropylene extruded for electrical insulation applications in electrical and electronic power systems equipment

End User applications

  • Solar Inverters and Combiner Boxes

  • UPS / Data Centers

  • AC Management and Climate controls

  • Low and Medium Voltage Switchgear and Power Distribution equipment

  • DC Power / Rectifiers / Telecom

  • White goods and appliances

  • Medical Applications

  • Power Electronics and Power Supplies

  • Consumer Electronics

  • Battery Chargers and Battery Packs



Made in the USA

  • Sold directly from The Gund Company and manufactured in the US, readily available in 7 locations in 4 countries.
  • PolyPro FR® from The Gund Company is a UL certified product: E228440
  • UL 94 V-0 rated in full thickness range of 0.010” – 0.125”
  • Extremely low water absorption
  • Suitable for outdoor use with respect to exposure to Ultraviolet Light, Water Exposure, and Immersion in accordance with UL 746C
  • Excellent fabrication and formability characteristics
  • Available in Black or White as a roll, sheet or fabricated part
  • Offers temperature resistance to 110 °C per UL testing
  • Provides a lower cost alternative for designs incorporating the use of materials such as Formex®, Nomex® 410, Valox, Mylar Polyester Film, Vulcanized Fibre, Voltoid, and Quin-T products
  • Excellent Dielectric Breakdown strength

How can you process/convert PolyPro FR®?

  • Die Cutting – Steel Rule Die, Rotary Dies
  • Laser or Water Jet Cutting
  • Heat Forming
  • Thermoforming
  • Machining – CNC Mills and Turrets
  • Printing
  • Welding
  • Joinery Methods
  • Lamination, Pressure Sensitive Adhesives (PSA), Aluminum and Copper foil

The Gund Company offers all the conversion processes mentioned above in 7 of our facilities across 4 countries

Common Applications for PolyPro FR®

  • Phase-to-Phase Barriers
  • Fuse Board Insulation
  • Switch Insulation
  • Terminal Insulation
  • Fuse Clip Insulation
  • Air Duct Baffles
  • Formed Channels
  • Ground Insulation
  • Chassis / Enclosure Liner
  • PCB Insulators / Liners
  • Insulating Spacers
  • Insulating Shields
  • Bus Bar Insulation
  • Capacitor Insulation

PolyPro FR® from The Gund Company is a UL equivalent to ITW Formex GK®. PolyPro FR® offers a significant cost advantage as well as numerous other advantages over common flexible materials in the industry.

PolyPro FRITW Formex GK®Vulicanized
Duroid D-100 FRMylar PET FILMNomex Aramid Paper


Lexan FR 700 Polycarbonate
FlammabilityUL 94 V-0 UL 94 V-0 UL 94 HB UL 94 V-0 UL 94 HB UL 94 V-0 UL 94 V-0 UL 94 V-0
Dielectric Strength2,000 VPM 1626 VPM 215 VPM 200 VPM 1,400 VPM 700 VPM 400 VPM 1500 VPM
Tensile Strength5,200 psi 4,400 psi 14,000 psi 12,000 psi 25,600 psi NA 7,500 psi 11,000 psi
Temperature Index110°C 115°C 110°C 90°C 130°C 220°C 140°C 130°C
Water Absorption0.01% 0.06% 66% 40% 0.01% 20% .04% .28%
Relative Cost100% 129% 106% 123% 127% 687% 276% 238%