Rubber Inserts for Metal Retaining Clips

To service the needs of our automotive customers, CRG supplies rubber inserts and cushions for a variety of metal clips, clamps and brackets used to secure lines and wiring in vehicles. The inserts we supply allows the clip to securely route and support a fluid line or cable, while providing a protective cushion that shields against abrasion and dampens noise, vibration and harshness (NVH).

Rubber inserts for metal retaining clips: automotive applications

Metal retaining clips, clamps, brackets and straps are often used to route and secure lines and cables in a variety of automotive applications, including the following:

  • Electrical wiring and cabling

  • Transmission lines

  • Brake lines

  • Power steering lines

  • Fuel lines

  • HVAC and windshield washer fluid lines

The metal retaining clips used in these applications often contain a rubber insert or cushion that surrounds the line or cable fastened by the clip.  The insert performs two essential functions: securing and protecting the line or cable as it is engaged by the clip, and suppressing any NVH (such as squeaks or rattles) that may be generated by movement of the line or cable as it passes through the clip. Because clips and their inserts can be exposed to vibration and stress, as well as chemical attack by moisture and aggressive fluids, it is necessary to choose insert materials that are well-matched to the application requirements. In addition to the design of the clip itself, the type of material chosen for the rubber insert is critical for ensuring problem-free performance.

Rubber inserts for metal retaining clips: materials

In producing rubber inserts for metal retaining clips, CRG draws upon an extensive portfolio of materials. While some applications can be serviced with inserts made from standard-grade elastomers such as EPDM, other applications require the use of more advanced materials such as fluoroelastomers (FKM or Viton®), Vamac®, Aflas®, TPE (Thermoplastic Elastomers), and TPV (Thermoplastic Vulcanizates).

Inserts made from FKM, Vamac® and Aflas® service applications involving temperature extremes and exposure to aggressive fluids and chemicals. TPV compounds represent the next step up in performance for Thermoplastic Elastomers (TPE). TPV compounds combine the characteristics of vulcanized rubber with the properties of thermoplastics. Most TPV compounds are a vulcanized combination of fully cured EPDM particles encapsulated in a polypropylene matrix. TPV compounds offer superior performance compared to standard TPE's, as well as providing enhanced resistance to extreme temperatures, chemical exposure, and harsh environments.

Criteria that should be considered when selecting a material to serve as a rubber insert include the service temperature range, chemical, UV and moisture resistance required, the compression set resistance needed, flame retardance and safety requirements, and manufacturability, as this can directly affect part cost.

Rubber inserts for metal retaining clips from CRG

CRG rubber inserts for metal retaining clips are custom produced to customer specifications for each application. We work with each customer early in their project to assist with part design and material selection. Parts are developed to meet all quality standards using a Production Part Approval Process (PPAP).

In the production phase of a project, CRG uses proven processes while adhering to recognized quality standards, such as ISO 9001:2015, to ensure reliable and consistent part quality. In every project, we maintain our commitment to 100 percent on-time delivery, whether utilizing demand-pull replenishment or JIT scheduling.

CRG supplies parts which meet ASTM D1056 line call-outs, as well as the material specifications of major OEM’s, including those of General Motors, Ford, Chrysler, Nissan, Mazda, BMW, Honda, Toyota, Volvo, and Mercedes-Benz. In those cases where a new specification is required, we work with our supply chain partners to develop an appropriate solution that meets or exceeds all requirements.

To find out more about the rubber inserts for metal retaining clips which CRG can supply, please contact our sales department at