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  • Writer's pictureBen Kilbourne

New Pack Fabrics

Updated: Nov 4, 2023

Fabrics Old and New

DCF (Dyneema composite fabric) hybrids and X-Pac fabrics have become ubiquitous in the ultralight backpacking world, and for good reason. DCF hybrids are light, waterproof, can be seam-taped, and have good tear strength. X-Pac is pretty durable, waterproof, comes in many thicknesses, and every color imaginable. For these reasons, Superior Wilderness Designs has built packs with both DCF and X-Pac and still regards both as great fabrics. But there was room for improvement.

SWD is now building packs with several new fabrics from the ECOPAK line by Challenge Sailcloth: EPX200, EPLX200, Ultra200X, Ultra400X. and Ultragrid.

I've had a chance to test some of them this year and am impressed so far. But I began to realize that some people often don't understand the possible benefits of these new fabrics when I try to explain them. With that in mind, the purpose of the following paragraphs is to answer these questions: Are the ECOPAK fabrics really any better than X-Pac or DCF? If so, how are they better?

Testing the Rugged Long Haul 50 in the Wind River Range

Out with the X-Pac

Superior Wilderness Designs has been using X-Pac VX07 as their standard light and inexpensive fabric for a long time. Made by sailmaker Dimension Polyant, X-Pac VX07 has a 70d nylon face laminated to a polyester x-ply, a 0.25 mil polyethylene terephthalate (PET) waterproof film, and a 50d taffeta backing. It weighs 4.8 oz/yd².

SWD also used X-Pac VX21 and VX42 on their rugged packs. X-Pac VX21 has a 210d nylon face and VX42 has a 420d face. These face fabrics are also laminated to an x-ply, a 0.25 mil film, and a 50d backing. The VX21 weighs 6 oz/yd², and the VX42 weighs 8.4 oz/yd². Abrasion resistance, measured using the Taber D3884 abrasion test, is 500 cycles for the VX21 and 1,700 cycles for the VX42.

Out with the DCF Hybrids

SWD has been using DCF hybrids on the ultralight versions of packs. DCF, previously known as Cuben Fiber, is a laminate fabric consisting of crisscrossing strands of Dyneema or ultra high molecular weight polyethylene (UHMWPE), sandwiched between thin polyester films. To use this fabric on packs where more abrasion is expected, a 50d or 150d plain-weave polyester face fabric is laminated to it. The 50d version weighs 2.92 oz/yd² and the 150d version weighs 5 oz/yd². On the Taber abrasion test, the 50d registers 500 cycles.

And in with the ECOPAK EPX

The X-Pac fabrics have been replaced by two exceptional fabrics from Challenge Sailcloth, ECOPAK EPX200 and EPX400. Most importantly, the EPX fabrics are made from 100% recycled polyester components. This is a big deal because the energy used to recycle polyester is far less than the energy used to create new nylon. Moreover, the type of nylon that X-Pac is made out of--nylon 6.6--is essentially impossible to recycle because it is constructed from two different molecules. Experts refer to the attempt as trying to unbake a cake.

EPX200 has a 200d polyester face fabric and the EPX400, as you might think, features a 400d polyester face fabric. Beneath the face on both fabrics, there is a 45° CrossPly, and sandwiched on the other side is a 70d ripstop backing. This ripstop backing increases seam strength considerably, in comparison to X-Pac seams. The EPX200 weighs 5.9 oz/yd² and the EPX400 weighs 8.95 oz/yd². Abrasion resistance on the EPX200 is about 500 cycles, whereas it's a very impressive 3,000 cycles for the EPX400.

The 2021 Long Haul featuring EPX fabrics

Reasons for Switching to ECOPAK EPX fabrics

  • EPX is made from 100% recycled polyester components, so it is better for the planet

  • Far less energy is used to recycle polyester than to create new nylons

  • Every yard of ECOPAK saves over one pound of CO2, compared to nylon pack fabric

  • CO2 emissions from manufacturing this recycled polyester are 50% lower than nylon

  • ECOPAK contains no harmful TPU, PVC, DWR, or other coatings

  • EPX has better abrasion resistance than X-Pac

  • EPX will increase the seam strength of the pack

  • EPX has a similar weight to its X-Pac counterparts

  • The overall cost of the pack remains about the same

  • EPX is 100% waterproof just like X-Pac

And in with the ECOPAK EPL Ultra

The DCF Hybrids have been replaced by some really impressive fabrics from Challenge Sailcloth: ECOPAK EPL200 Ultra, EPL400 Ultra, and EPL800 Ultra. You may sometimes hear people referring to these as UltraWeave or sometimes just Ultra. The face of these fabrics is woven 200d, 400d, or 800d UHMWPE. This is laminated to a 0.5mil polyester film for waterproofness and to keep the weave of the face from shifting around. This film is 100% recycled and has excellent UV resistance.

The EPL200 Ultra will be replacing the 50d DCF hybrid on SWD's ultralight packs. It weighs 3.5 oz/yd² to the 50d DCF's 2.92 oz/yd², so it is only ever so slightly heavier. Pair that with the fact that the Ultra 200 tested to an amazing 3,800 cycles on the Taber test, whereas the 50d DCF is around 500 cycles.

Made from EPL400 Ultra and EPL800 Ultra, the new Rugged Long Haul 50 is seriously bombproof

A closeup look at the EPL200 Ultra

The EPL400 Ultra (4.65 oz/yd²) will now be used for the body of SWD's rugged packs because it is actually a little bit lighter than the 150d DCF (5 oz/yd²) and significantly lighter than the VX21 (6 oz/yd²), or the VX42 (8.4 oz/yd²) previously used. EPL400 Ultra tested to a ridiculous 7,600 cycles on the Taber test, which is far higher than anything yet mentioned. The EPL800 Ultra will be used for the bottoms of these rugged packs. It weighs 8.1 oz/yd² and went an absurd 10,500 cycles on the Taber test.

Reasons for Switching to ECOPAK EPL Ultra fabrics

  • EPL Ultra has far better abrasion resistance than either X-Pac or DCF hybrids

  • The overall cost of the pack remains about the same as packs made with DCF hybrids

  • It is lighter than either X-Pac and DCF hybrids

  • 100% waterproof just like X-Pac and DCF hybrids

  • EPL Ultra is made from 33% recycled polyester components, so it is better for the planet

  • Far less energy is used to recycle polyester than to create new nylons

  • Every yard of ECOPAK saves over one pound of CO2, compared to nylon pack fabric

  • ECOPAK contains no harmful TPU, PVC, DWR, or other coatings

  • CO2 emissions from manufacturing the recycled polyester used for the film backing are 50% lower than nylon

Parting Thoughts

After using a Rugged Long Haul 50 constructed from EPL Ultra fabrics on my last few trips, and after looking at all of these spec comparisons, I tend to believe that the ECOPAK fabrics will be around for a while. Other brands such as Waymark Gear, Atom Packs, Pa'Lante, and many others are now constructing packs out of ECOPAK materials, and it's probably only a matter of time until we see other companies using them as well. In the meantime, I'm going to go drag my Rugged Long Haul 50 through the desert and see how it goes. I expect it will take a lot of butt-slides down slickrock to really find out how durable the EPL Ultra is, but I intend to do my best.

Written by Ben Kilbourne

You can check out more of Ben's work on his blog

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John Bullock
John Bullock
Feb 17

What about EPLX200? SWD is using it—how does it compare to the fabrics discussed here?


Oct 03, 2021

Glad to find such a comprehensive comparison of all the common materials in UL packs, helped with choosing my next pack!

Ben Kilbourne
Ben Kilbourne
Oct 04, 2021
Replying to

I'm glad it helped! Which fabric did you decide on?

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