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Oni 527 Tapered Secret Denim Review

When I set out with the goal of reviewing the Oni 527 jean, I hoped to find out as much information on the model as possible in order to provide an accurate review. Therefore I contacted Blue in Green, the sole American distributor of the denim and the location where I had purchased the jeans. Store owner Gordon Heffner responded with the following:

…the information we’ve listed is all the information that was provided. As the name suggests most of the info is held secret so as to not be copied. As for Oni in general it’s sort of the same thing. What I can tell you is that it’s a one man operation run by a gentleman who’s family has been at the forefront of the domestic denim scene in Japan since it started. He’s a master of his craft that shies away from the spotlight and likes to let the denim do the talking, so to speak.

Heffner directed me to a blog of one of his customers who had written out an overview of Oni’s roots. To paraphrase, Oni is run by the son of the founder of Oishi Trading Company, a part of Canton Mills, one of the first mills in Japan to start making jeans. He doesn’t do interviews or any press at all, he focuses denim manufacturing and little else. All of this makes a thorough review of the denim tricky. But after putting these jeans through the ringer for a year, I’ve had plenty of time to observe.


  • Name: Oni 527 Secret Denim
  • Fabric: ????
  • Weight: 20oz.
  • Fit: Tapered
  • Unique Features
    • Deerskin leather patch
    • Single needle back pocket arcs
  • Available for $325 at Blue in Green



Blue in Green lists the Secret Denim a low tension 20 Oz. weave with a mid/high rise and a tapered leg. The warp is rope-dyed in indigo, while the weft is dyed beige to give it a color closer to wild growing cotton. The patch is made of deerskin leather and the expected shrinkage in the raw version is 6-8%.

The first things you notice about the jean are its color and the characteristics of the jean’s weave. The 527 is a couple shades lighter than your average raw, the beige weft emphasizes the indigo’s green cast, while the selvedge line is a muted pink. I’ve always met the idea of pink selvedge with a bit of trepidation, but in reality it’s much more subtle. With a fair amount of nep, hairiness and slub, it looks almost like they’re woven with wool. These won’t make any lists for being on the extreme for any of these characteristics, instead opting for a nice restrained blend. It’s a cool aesthetic, very different than what most people are used to and stands out in conjunction with the color.

Prior to washing, the weave was very loose. You could see light punch through the fabric at the right angle. But once these were given a hot soak, the initial shrinkage was close to the 8% prediction, putting the Secret Denim on the higher end of the shrinking scale, but Blue in Green’s One Wash chart matched up well with my measurements after they dried. Keep in mind, each batch definitely has some minor discrepancy so make sure that everything is up to date.

Heavier weights usually equates to more misery when breaking in, but not so with the Secret Denim. They had a rough feel, for sure, but they were nowhere near as uncomfortable compared to what is normally expected from heavy raws. I had to double check with BiG to make sure they hadn’t sent me a washed-once pair by mistake. They assured that this wasn’t the case; the loose weave reduces initial stiffness and thus adds to initial comfort. This makes the 527s a good option for anyone looking to ease into heavyweight denim.


At 8 months

Oni keeps it classic and minimal. The 527 uses a combination of single and double needle stitching with an overlock stitch on the inseam and the yellow and orange thread contrasts well to the color of the denim itself. Other than the standard selvedge outseam, the only other id on the jean is hidden inside the coin pocket. Copper rivets are unmarked externally and the steel donut buttons have the standard laurel leaves. The pocket bags are a heavy and smooth, with no piling noticed with wear.

The most flashy part of the jean is without question the pocket arcs. Ever since Levi clamped down on copyright infringement, Oni has used a sharp, sweeping arcuate that likens itself to a sort of curved throwing weapon. It’s polarizing for many people, leading some to even rip it out. Blue in Green now features an exclusive narrow version of the arc (this version appears on other Oni models), but anywhere else you’ll find the broader original. It’s become less prominent as the jeans have worn in, but nevertheless people seem to love it or hate it. As far as the pocket location itself, they seem about half an inch to an inch further from the center than the average placement.


As far as fit goes, it’s one of the best contemporary fits to be found from a Japanese brand. Oni’s earlier jeans were beloved for their denim, but many decried the vintage fits that were too baggy for western denimheads.

More recent fits like the 527, however, have garnered little criticism. Every fit pic I’ve seen of these jeans has been flattering. The top block leaves enough room for a wide range of movement and tapers down to a moderately narrow hem. The only issue I’ve had is that the seat could be tightened up a hair to remove some sagging. If you’re looking for a good comparison to these in terms of fit, think Samurai’s 710xx with a minimally heavier taper.


One Year Later…

Close up of Current Thigh

Close up of Current Thigh

For over 13 months, these were the primary jean in my rotation until I placed in reserve for a denim contest. They didn’t see extremely heavy wear due to a fairly sedentary life, but they were worn on hikes, when hauling heavy goods, and the occasional bike rides. They were washed three times and soaked twice. Now the nep and the hairs of the raw denim are gone. Soaking and washing bunched the slub further, creating a rough surface but a knit-like feel on the inside.

They’ve held up well except for where I keep my cell phone (the oversized Samsung Note 2) and a small hole in the crotch. The latter hole wasn’t due to a weak fabric but rather their rough texture. Normal thigh friction created a threadbare hole about the size of a quarter at the year mark. They never showed any signs of risking a true blowout. Either way, Denim Therapy cleaned both spots right up. Considering that the denim is in great condition everywhere else, I could see these lasting well into the foreseeable future.


I’d call the fade rate moderate. The first indigo shed along the wallet outline at around week one or two, the thighs came shortly thereafter and by the four month mark they were starting to show real progress. At about nine months, after the second wash, they hit the point every denimhead looks forward to – the day where all the persistent wear really has paid off.

The third wash came too soon because I had to send them in for repair, but the I’ve been very happy with the fades. As per usual, pictures don’t do them justice because of the fine details lost in the shuffle. Due to the loose weave, there isn’t very much sharp creasing, instead lending itself to a more vintage all over fade.

Oni 527 after a soft 13 months wear

Oni 527 after a soft 13 months wear

Whoever is the maker behind the denim madness at Oni has come up with yet another great weave. These aren’t as slubby, hairy or contrasty as some jeans, but they ooze character and have a jack-of-all-trades feature set. They kept me warm in the winter, yet breathed enough to stand up to the heat. They caught people’s eyes yet never felt garish or flashy.

Overall, I have zero regrets with their purchase. Oni doesn’t produce a ton of jeans, nor do they market themselves at all. But their high level of quality and drive to carve their own path puts them on par with any of Japan’s raw denim titans.

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