U-Style Flexible Duct Connectors

Flexible Specialty Products’ U-Style flexible duct connectors are constructed from PTFE-coated fabric or 100% PTFE fabric. They’re capable of handling temperatures up to 1000F. The integral molded flanges provide simple installation and the flex connection can be fabricated in any size or shape. The fabric flanges are typically pre-punched to match the mounting flange hole pattern and are provided with backing bars for attaching the fabric flexible connector to the adjoining flanges. All flex duct connectors are custom-designed and manufactured to match fan inlets, fan outlets, or custom transitions to adjoin two different-size pipes or ducts.

U-Joint formed flange

This lightweight and economical flexible duct connector is an excellent solution to compensate for movement due to thermal growth, vibration, misalignment, and wind loads. These are an excellent choice for fan flexible connectors to solve vibration isolation problems as well as any application requiring a slip-in connector.  Many additional accessories are available to compensate for abrasion, sound transfer reduction, and temperature protection.

Flexible Specialty Products custom-manufactures this type of flex duct connector to exact customer requirements.

Contact a sales representative at FSP today to discuss your application.


U-Joint Formed Flange Rect U 1000

Flexible connectors can be provided in custom-manufactured sizes and length to meet your specific requirements. Transitions, cold-offset, and convex designs are available to meet demanding flexible connector applications.


Many additional accessories are available to compensate for abrasion, sound transfer reduction, and temperature protection. Contact a sales representative at FSP today to discuss your application.

  • Backing Bars

    Backing Bars

    Backing bars, or clamp bars, are steel bars or angles used to mount or clamp the fabric to the frame work or duct flange. FS products manufactures backing bars in a variety of materials and thickness as required based on the specific application. The backing bars are shipped as full rings or picture frames when practical. Holes are pre-punched to match the adjoining ductwork to allow quick and easy installation of our U-Joint Formed Flange expansion joints. Backing bars are typically shipped painted with our standard high-temperature silver primer, but custom coatings and galvanizing can also be applied.

  • Flow Liner

    Flow Liner

    All expansion joints can be supplied with various configurations of flow liners.  Flow Liners can be supplied as bolt-in unit design, single, tapered, overlapping, and floating.  The primary purpose of flow liners is protection of the internal insulating materials from abrasives in the gas flow.  They are also used to secure the internal accumulation pillow in place as well as to provide a laminar flow in the area of the expansion joint. Flow liners need to be designed to allow full system design movements while providing the necessary protection and support.  Many materials of construction are available including carbon steel, stainless steel, Corten, AR Plate, and special alloys.  Check with FS Products to see how flow liners can increase the life of your expansion joints.

  • Gasket Flexible Speciality Products


    Gasket are recommended for any metal to metal installation. We stock several widths of fiberglass gasket tape as well as PTFE coated fiberglass products. Our extruded PTFE gasket tape is ideal for fabric to metal installations or when a highly compressible, chemical resistant seal is needed. Let us provide all of the gaskets required for your expansion joint installation to avoid costly delays and misplaced parts needed during installation.

  • Fasteners


    Flexible Specialty Products can provide any necessary mounting fastener for your expansion joint application. We will properly size the fasteners and provide standard grade or any specialty fastener required. The fasteners will be packaged with the expansion joint shipment to assure the fasteners will be on-site when needed to avoid costly delays or misplaced parts.