Redback Low Elongation

High elongation is great for Slinkys, but it’s not good for woven and composite cord strapping. Too much elongation causes say and can prevent buckles from staying closed and loads from staying tight. And when straps stretch too much, their ability to resist impacts is reduced. So high elongation strapping can be very dangerous where a high impact resistant, low elongation strapping like Redback is required.

ASTM International and the Association of American Railroads (AAR) require woven and composite cord strapping to have between 9% and 15% maximum elongation at break. Redback low elongation woven strapping is typically between 12% and 13% and Redback low elongation composite strap is typically between 10% and 11%. And redback strapping has high modulus of elasticity. So as it is stretched, it fights back exponentially like an industrial shock absorber to return to its original shape.

By contrast, a lot of woven and composite strapping on the market can have 50% to 100% more elongation than Redback. Here’s a comparison of AAR approved Redback grade 4 composite strapping and the grade 4 composite strapping from the leading U.S. manufacturer. As you can see, the competitor Strap had 23 ½% elongation compared to Redback at 11%.

That’s more than twice the elongation and clearly does not meet ASTM international or air requirements. If you would like to secure your load with dependable, high impact resistant, low elongation strapping, give us a call or check us out on the web at

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