April 03, 2023

Getting to know X-Pac® X4 Fabrics

For those aware and a fan of X-Pac® fabrics, it may be because of Dimension-Polyant’s distinctive X-Pac® X4 collection inspired from the company’s leading sailcloth technology.

Noticing a fit for the X4 laminate technology in the outdoor industry – most notably for backpacks and bags – Dimension Polyant introduced its X-Pac® X4 collection with success in the mid-2000’s. Since then, the X4 collection, the most popular in the X-Pac® line have been adopted by major international outdoor, every day, and lifestyle backpack and bag brands due to its durable, high-performance benefits, and unique textile aesthetic.

Taylor North Head of Technical Fabrics, Dimension-Polyant US and Jonathan Mersereau, Sales Manager, Dimension-Polyant US, share their perspective on the significance of the X-Pac® X4 collection in the outdoor and lifestyle markets and where they see it evolving.

What inspired Dimension-Polyant to develop the X4 fabric collection for backpacks?

The X4 collection was developed from our sailcloth laminating capabilities. At Dimension-Polyant we have a unique laminate process that had been extremely successful in the sailcloth market. Wanting to bring highly technical laminate textiles to other industries, outdoor backpacking was a logical fit. Using materials like nylon and polyester to better align with traditional pack fabrics, Dimension-Polyant set out to deliver an outdoor pack fabric with unmatched strength to weight ratios.

Borrowing from sailcloth technology, X-Ply® fibers were introduced to the fabric to help with off-axis, dynamic forced.  For pack fabric, however, load is rather stable and rests upon the attachment points of the pack – the shoulders, hips, and handles. The 22.5° orientation of the X-PLY fibers help spread the load from your hip to the opposite shoulder. Laminating films to woven fabrics woven fabrics create a 100% waterproof material and achieves more structure than an ordinary fabric.

Lastly the backing taffeta, which distinguishes X4 styles from other X-Pac® fabrics, again borrows institutional knowledge from sailcloth where it improves durability of laminated films. Through this process the X4 range was born and has become a staple of the X-Pac® brand ever since.

How has the X4 collection evolved? 

At Dimension-Polyant we are continually developing new products, improving processes, and optimizing equipment. The X4 products are no different, whether it be tweaking our adhesive formula for better performance or making wider fabrics to optimize cutting efficiency for our customers. Recently the X4 fabrics have been developed to utilize post-consumer recycled polyester in the X-PLY fiber and recycled backing taffeta. We plan for the X4 products to be certified Climate Neutral by the end of 2023.

What makes it unique?

The X4 product line is the original, legendary, X-Pac® construction. The first to combine the durability of a nylon face fabric with strategic fiber reinforcement, internal film and backing taffeta. The result is a robust fabric that is the “Swiss Army Knife” of fabrics; it does everything and works when you need it to. Originally developed for the rigors of alpine expeditions, the X4 product line has been proven in the backcountry and is now accepted as the standard for quality and performance for bike packs, everyday carry (EDC), and lifestyle packs.

What is the most popular fabric in the collection and why do you think it is?

The most popular fabric is VX21, followed closely by VX42. VX21 uniquely balances it’s strength to weight ratio with impressive tear and tensile resistance as well. It’s an excellent all-purpose fabric. The lighter 210 denier nylon face fabric makes it extremely versatile, and because of that, we offer it in the widest array of color options. In addition, we have certified this fabric as 100% climate neutral and part of our cleenTEC® program. Our cleenTEC® seal signifies X-Pac® fabrics made with recycled, bio-based, or sustainably sourced materials while being 100% climate neutral, making it that much more appealing for brand partners looking to source responsible materials. 

Can you share some unique products that some of your customers have made with the fabrics?

We have seen some unique designs for sure! I have worked personally with a brand partner who used VX21 for the exterior of canyoneering packs, which puts some serious stress on the fabric. We saw some stress tests and were amazed with how well the fabric held up! Lately we have seen an explosion in the travel pack space as people return to pre-pandemic travel levels. The rugged nature of a heavier 420 denier face fabric found in VX42 is very popular as it holds up to the rigors of air travel. There are also a lot of smaller designs like fanny packs, slings, dopp kits, and more that utilize all our colors, or use lighter fabrics like VX07. Our VX03, of late, has become a popular option for liners within bags, as it is more durable than standard materials used for bag liners.

Why do brand partners want to adopt X4 fabrics into their product lines?

One of the advantages of our X4 line versus others is that it features a backing taffeta. While it may not be important to every design, the backing taffeta in a lot of instances acts as an internal liner that could potentially eliminate the need for liners inside of packs. The taffeta acts as a protective layer against the mid-layer of film which can help extend the life of the fabric. So not only is it a durable face fabric material, but the backing is also strong as well.

Are there plans to expand the x4 collection? If so, what is in the works?

We are always experimenting and there should be new development of X4 fabrics in 2023. For example, we are working on bringing our new RX line, 100% recycled polyester fabric – currently only available as an X3 style with no backing taffeta – to the X4 line by adding recycled polyester taffeta to enhance the fabric. This would provide both a 4 layer and 3-layer option for brands and partners looking for the advantages of X4 styles with the sustainability story of RX. Another program we are working to expand is our cleenTEC® seal. VX21 is currently our only X4 style that qualifies for the cleenTEC® seal but we are working towards bringing more styles like VX42 and VX07 into the fold as well.

Jonathan and Taylor will be attending the Functional Fabric Fair in Portland, OR this coming April 4th-5th. If attending and want to meet up, please let us know by contacting us at For more information on our X-Pac® fabrics, please contact us.