Quanex Building Products Corporation is an industry-leading manufacturer of components sold to Original Equipment Manufacturers (OEMs) in the building products industry.  

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Thresholds and Seals

High-Performance Thresholds

Composite Thresholds incorporate the patented ImperiSeal™ technology, a continuous filament that positively seals the adjusting rail to the deck of the sill, thus eliminating any chance of water intrusion through the threshold. The cellular PVC rail is extremely resilient to long-term exposure to temperature changes, wind, and snow.

  • Meets code and design requirements
  • Precision-engineered rails adjust upward (3/16”) and downward (1/16”) using flush screws, while the rail interlocks with a high-dam aluminum sill
  • Available in mill and bronze finish

Maximize Door System Performance with Door Seals

Help your thresholds and astragals reach their maximum performance potential with Quanex’s Imperial weather-sealing solutions for doors that are designed to combat the straw effect during high-wind or stormy conditions.

  • Available in beige or bronze color and bulb or fin style.


Three-Point Locking System

Fight corrosion and forceful entry with Quanex’s Imperial MPLS3 stainless steel three-point locking system, designed to withstand the elements and work in tandem with quality weather stripping products.


Low-maintenance meets high performance with Quanex’s precision-engineered Triple Seal and sustainable StainRite and White French door astragals.