July 19, 2021

Zipper Updates: YKK Water Repellent Racquet Coil Zippers

Zipper Updates: YKK Water Repellent Racquet Coil Zippers

Recently, we’ve been using more YKK Water Repellent Racquet Coil zippers instead of our usual YKK Aquaguard® zippers. Most notably, the RC DWR (racquet coil with durable water repellent) zippers have appeared on the Shadow Guide, LGD, and Design Lab Packing Cube Shoulder Bag. Our upcoming Techonaut will debut with the same RC DWR zippers.

Below are photos of each zipper in an effort to help future-you determine which of your bags have which zippers:

Racquet Coil Zipper in the Techonaut 30

The #10 DWR Racquet Coil Zipper on the main compartment of the Techonaut 30. 

#10 Aquaguard zipper on a Synapse 19

The #10 Aquaguard® zipper on a Synapse 19. 

As we transition bags such as the Synik 30, Synik 22, Synapse 19, Synapse 25 and other major bags and packs to RC DWR, those pages will display lists of which color combinations have RC zippers and which have Aquaguard® zippers. We think the majority of folks will be happy with either the DWR RC *or* the Aquaguard® (they’re both great, high quality zippers) so these lists are just for those of us who may have a preference for one or the other.

So, then, what are the reasons behind the transition? We looked back at our materials meeting notes and here's the scoop:

First up, Aquaguard® zippers require a little bit of an extra tug to open and close due to the thickness added to the zipper tape by the urethane coating that makes them so darn water repellent — and we've heard from folks over the years who aren't fans of that. 

Next, the zipper sliders on Racquet Coil zippers are slightly smaller and, in some applications, this makes a noticeable difference. An example of that is the exterior access laptop compartment of the Synik 22 / 30, Shadow Guide 23 / 30, and the upcoming Techonaut 30 / 45: you may be able to more comfortably insert and remove your laptop thanks to that teeny bit of extra space offered by the smaller slider. It's especially noticeable with the Syniks.

We took a look at our notes from our meetings re: RC zippers and found this from a meeting in January 2020 (feels like a decade ago!)

We would also change the laptop compartment zipper of the Synik to be #8 DWR RC and likely sew it in reverse and apply a loop through new style of cord pull — this is an often-used compartment, so makes sense to switch it to RC plus the reverse will provide a softer entry for the laptop, the actual opening for the laptop will be even a little bigger, and the new pull will tone down the noise and the overall look will be more minimal.

Finally, the surface resistance is slightly better. Racquet Coil zippers are coil zippers that are engineered by YKK specifically for luggage and bags: applications that are subjected to more abrasion than, say, clothing. This doesn't, in any way, mean that Aquaguard® aren't durable, quality zippers that last a long time: they do! It's just that RC zippers are described by YKK as being that much more abrasion-resistant and thus lasting longer. As you can probably tell by reading this post, we don't take or make these decisions lightly: when pondering the possibility of transitioning to RC zippers, we reached out to friends of ours in the bag industry — those with materials expertise as well as those who also have bag companies and design/make/sell bags to the general public — and asked for their opinions and experience around the use of RC zippers. The people we spoke with said they're good quality zippers that stand the test of time, and one person noted that their transition to RC reduced the number of bags that needed repair. 

The improved abrasion resistance was actually what prompted us to begin discussing the possibility of bags utilizing RC zippers. If you've read this far, you might also remember back when a few folks experienced some strange and unusual wear on the main compartment zippers of a few bags. Though it was only a few instances, we thought the most responsible thing to do would be to just change the attachment points for the shoulder strap. (Read our blog post Updates to Snaphook Attachment Point Placement for more about that.) Folks then shared that they weren't fond of the new attachment point placements. Here's another excerpt from that January 2020 meeting in which we discussed RC zippers:

The feedback about the PCSB zipper (people didn’t like the new attachment points) prompted us to take another look into the world of zippers. The nylon toothed zipper is practically indestructible, but so far, the Forum moderators to whom we sent samples didn't like it: it’s loud and doesn’t corner well. Still, we think it will have some unique applications for us. 

What is much more promising is the DWR RC zipper — it’s a special version of racquet coil zipper with a YKK applied DWR. We received a test sample and, according to our tests, it performs very well when it comes to water resistance — on par with Aquaguard.

Now, in mid-2021, after moving forward with the RC zipper transition and reevaluating the original issue, we have determined that the increase in durability offered by RC zippers will allow us to transition back to the original shoulder strap attachment points of bags such as the Packing Cube Shoulder Bag, Side Kick and Daylight Briefcase by the end of this year. Though, to be fair, we can't credit this switch entirely to the RC zippers: we now believe our decision to change those attachment points to prevent wear on the zipper of those particular bags was a bit overboard given there were only a few instances of that resulting in an issue.

Stay tuned for more news on that as we get closer to that transition happening. We know that some folks prefer the current strap attachment style, and our goal will be to give everyone a heads-up so they can purchase the current style or wait for the previous style to be offered.

And we still do plan to find a use for that nylon toothed zipper: we're quite fond of it ourselves.

Interestingly, it turns out that our DWR Racquet Coil zippers are less expensive than Aquaguard® zippers (though slightly more expensive than non-DWR Racquet Coil zippers.) This is a rare instance in which the material choice that we think will offer the majority of folks the best experience in joy of use, long-term abrasion resistance, and water-resistance is also a less expensive, though very far from the least expensive, option. That reduction in expense will end up serving to offset a fraction of the new cost increases we're currently absorbing, which is a nice twist of fate that we could not have foreseen when we began considering a transition to RC zippers.

And, of course, if you've followed us over the years, you know that we don't make materials decisions based on price, though we felt this aspect worth mentioning. Funny enough, we'd sometimes get feedback from folks who told us that our Aquaguard® zippers were cheap and poor quality zippers precisely because of the extra tug they require. 

Over time, Small Cafe Bag, Medium Cafe Bag, Maker's Bag, Side Kick, Side Effect, Pop Tote, Brain Bag, Daylight Backpack, Packing Cube Shoulder Bag and Paragon will all effectively receive a zipper upgrade as they transition to our DWR RC zippers, as the previous #8 and #10 zippers utilized in those bags didn’t have any sort of coating or DWR (Durable Water Repellent) treatment.

To recap: we’ve been testing and using DWR RC zippers for the last couple of years, and, in our own tests, we found that the water repellency of the Racquet Coil zipper treated with DWR to be on par with that of the standard coil Aquaguard® zippers. RC zippers don’t require that little bit of an extra tug to open and close: they zip open and shut quite smoothly, in fact. Though our Aquaguard® zippers are quite durable, RC zippers are reputed to be even more so. The smaller RC sliders give just a little extra room and sometimes that counts. Rereading this post as we proof it, we're struck by all of the materials changes that we make: it's a lot of work for us and it's a lot of change for both you and for us! Our intent is to offer the best quality bags in both materials and design. One way we can do that is to put a lot of thought, care, and consideration into our materials choices, and sometimes that means making changes based on our experience and testing that we think will result in a better bag.

We’ve updated our Materials Glossary entry on zippers with more information, if you want to dig even deeper.


Darcy - CEO - July 22, 2021

@David Floro Thanks for the recommendation. I’ll ask Tom, I bet he’s read it!

David Floro - July 22, 2021

If you haven’t read Robert Friedel’s book, “Zipper,” then you are missing the interesting historical tale told about what was the uneasy and unwanted novelty that is now the ingenious & ubiquitous part of daily life—the zipper!

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