Many waterproof and more durable ultralight backpacks are made with Dyneema Composite Fabric (DCF) or X-Pac, another high-tech laminate fabric similar to DCF but less expensive and easier to make backpacks with. Below, we explain the tradeoffs between these DCF and X-Pac in terms of durability, weight, cost, and water resistance so you can choose the backpack material that best suits your goals.
What is Dyneema Composite Fabric (DCF)?
Dyneema Composite Fabric or 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. This is the material that DCF shelters such as the Zpacks Duplex Tent are made of. To make this material applicable to pack construction where more abrasion is expected, some sort of face fabric needs to be laminated to it. Typically this means adding either a 50d or 150d plain-weave polyester to make a DCF hybrid fabric.
The two most common DCF pack materials in the ultralight backpacking industry are a 2.92 oz/yd fabric and a 5.0 oz/yd fabric. The 2.92 oz/yd DCF hybrid is a two-layer fabric consisting of Dyneema Composite Fabric laminated to a 50d plain weave polyester. This fabric is used on the main body of the Hyperlite Mountain Gear Southwest 3400, the Zpacks Arc Blast 55L Backpack, and the main body of the Mountain Laurel Designs DCF Exodus. The 5.0 oz/yd DCF is a two-layer fabric consisting of Dyneema Composite Fabric laminated to a 150 denier plain weave polyester. It is used on HMG’s larger capacity packs such as the Porter 4400 among others. It is also found on the back panel and bottom of the Mountain Laurel Designs DCF Exodus and the bottom of the Hyperlite Mountain Gear Southwest 3400.
What is X-Pac?
X-Pac is a material made by sailmaker Dimension Polyant. It comes in all sorts of weights, but I will focus primarily on one of them here, VX21, as it is the one most commonly found in the backpacking industry. There are several other varieties including VX07 and VX42 which folks will probably discuss in the comments. X-Pac VX21 has a 210d nylon face laminated to a polyester x-ply, a 0.25 mil polyethylene terephthalate (PET) waterproof film, and a 50d taffeta backing. It weighs 6.0 oz/yd. This ubiquitous fabric can be found on the Six Moons Designs Minimalist 2.0, the Hanchor Marl, many of the packs made by Superior Wilderness Designs, the Seek Outside Divide, among many, many others.
DCF vs X-Pac: Durability Comparison
X-Pac VX21 is one of the most common materials for pack bodies for several reasons. The 210d face fabric is pretty durable, resisting abrasion quite well. Recently I bushwhacked through a particularly dense part of the Sonoran Desert wearing the Yar Gear Mountain Drifter 38L which is made from a ripstop version of the VX21. I scraped through catclaw mesquite among other spikey plants for many miles, certain that the pack would show some residue of the experience by the end, but it did not, there’s virtually no evidence of the heinous bushwhack. I am very impressed, to say the least.
I wore the Six Moon Designs Minimalist 2.0 which is made from VX21 on a 35 mile Grand Canyon hike involving some bushwhacking and rock scraping and made the same observation, the fabric seems unchanged. While my Seek Outside Divide is made of X42 (420d face fabric) and not VX21, it has been through many years of bushwhacking and rock scraping and has some fuzziness to show for it but overall is still in excellent condition.
I used an HMG Porter 4400 (5.0 oz/yd fabric) for several years and never got a proper hole in it but it did start to become slightly “fuzzy” after a while. Moderate bushwhacking with my HMG Southwest 3400 (2.92 oz/yd fabric) resulted in some minor abrasion on the pack’s extension collar, but nothing too bad.
I hesitate to make any sweeping claims on durability because I’ve used both fabrics and both have held up quite well. Because of its 210d nylon face fabric, one might assume the VX21 would be more durable than either of the DCF hybrids. Some testers claim, however, that the raised X-Ply pattern increases wear in these areas. This has not been my experience, but I don’t want to rule it out either.
Because one of the main benefits of DCF is its incredible tear strength, DCF packs are likely stronger than VX21 packs in that regard. I don’t know that this matters all that much, however. I personally find abrasion resistance to be more important than tear strength when it comes to backpack materials.
The bottom line here is that cost and weight are better metrics for deciding between these DCF hybrids and VX21 fabrics. That said, it could be fairly safe to assume the much thicker X-Pac fabrics such as X42 and X50 will be substantially more abrasion resistant and substantially heavier than the DCF hybrids.
DCF vs X-Pac: Weight Comparison
The 2.92 oz/yd or 5.0 oz/yd DCF fabrics are both lighter than the 6.0 oz/yd VX21, but what does this mean in terms of actual final pack weight? Take the Superior Wilderness Designs Long Haul 50 as an example. Their DCF version, made from the 3 oz/yd fabric with a 5.0 oz/yd bottom, weighs around 22 oz with all extras removed. The VX21 version, which they call their Long Haul 50 Rugged, comes in around 26.5 oz with all extras removed. So, for the same pack, you’re saving somewhere in the vicinity of 4.5 oz by going with DCF. I can certainly see making this choice if you want to save as much weight as possible.
Note: Hyperlite Mountain Gear and Superior Wilderness Designs make many variants of the models listed above that only differ slightly, which is why we haven’t listed them all.
DCF vs X-Pac: Cost Comparison
In general, you can expect to pay more for DCF packs. To continue using Superior Wilderness Designs as an example, you will pay around $66 more for the DCF version of the Long Haul 50. $66 to save a quarter of a pound could be very worth it depending on your budget and the pack’s intended use.
DCF vs X-Pac: Water Resistance Comparison
Both fabrics are completely waterproof, the difference in the pack’s overall waterproofness coming down to the different ways these fabrics are sewn together. Because of the scrim on the inside of the VX21, it cannot be taped. DCF packs, on the other hand, can be taped resulting in fully waterproof bags.
For example, all of Mountain Laurel Designs DCF packs are completely waterproof, a pretty incredible feature for wetter trips. I love the idea of not having to deal with a pack cover or pack liner. Additionally, the polyester face fabric of the DCF hybrid tends to absorb less water than the nylon face fabric on the VX21. While I haven’t scientifically measured this, I have speculated that a sopping wet VX21 pack might weigh slightly more than a soggy DCF pack.
When is an X-Pac backpack better?
X-Pac VX21 is a popular pack material in the backpacking industry because it strikes a great balance between weight, durability, waterproofness, and cost. And colors – don’t forget colors!
Choose a pack made of this material if you want a very water-resistant but not completely waterproof pack with good abrasion resistance. Another great feature of VX21 is its white inner scrim, which makes finding dark items in your pack quite easy.
When is a DCF backpack better?
Choose a pack made of a DCF hybrid when a low pack weight and waterproofness are of utmost importance. If you don’t mind spending a bit more on these features, a DCF backpack could be for you.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.