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The Pen Slim - Indigo Raw 17.5oz Mammoth Selvedge


Slim fit, medium rise, 17.5oz raw Japanese 4-Way Stretch Selvedge, zip fly, premium leather patch, and custom-branded hardware. Made in USA.

These jeans are heavier fabric and they take time to break in. For a comfortable fit, we advise opting for one size up.


We are very excited to offer our first heavyweight denim! We pushed the limits of our 4-Way Stretch Selvedge to create The “Mammoth” 17.5oz 4-Way Stretch Selvedge. Nick Noguchi worked closely with a renowned Japanese mill to develop this one of a kind denim. For these new jeans, we went with a special Bordeaux Red selvedge ID, polished silver buttons, and a navy leather patch.

Heavyweight denim is uncommon because of how difficult it is to produce. Combining this heavyweight with our 4-Way Stretch Selvage results in a next level denim exclusive to Kato. This denim has the same look and comfort of our lighter 4-Way Stretch Selvedge, but is thicker and even more durable.

Why heavyweight denim? The thickness of the denim plays a big part in how the denim fades. The thicker the denim, the more pronounced the creasing will be. This creasing contributes to an increased contrast and definition of the fades. The stunning results of a pair of well worn heavyweight jeans is why denim connoisseurs around the world seek out these heavier denim weights.

The new “Mammoth” 17.5oz 4-Way Stretch Selvedge is available in Raw indigo denim and two distinct washes that have been carefully aged by hand. These three versions represent the different stages of denim jeans over the first several years of wear.

The original Raw indigo denim is a blank canvas for you to develop your own unique pair that ages according to your lifestyle and experiences. The Raw Indigo “Mammoth” is available in The Pen Slim, The Hammer Straight.


Fit & Size

Slim Fit | See Fit Guide here

Model is 6' and wearing a size 32.


Raw denim has up to 2% shrinkage while it would be 1% for washed denim after wash but they will also stretch out again by being worn over time.


If you are not satisfied with your purchase, You may return or exchange the items within 21 days from the date the order is shipped out.

Once your order with the hemming request is brought to our tailor, the order will not be refundable.

International orders (outside from the US) are not eligible for returns or exchanges.

Check here for more details.

the details
4-way stretch selvedge
Premium japanese fabric
made in usa
ykk & premium hardware
vintage inspired

Customer Reviews

Based on 4 reviews
Marc Manix
Oldschool Denim I've Been Looking For

This denim is solid and feels like the vintage / old school denim from years ago that you can no longer find. I don't like all the super soft and stretchy "denim" that one finds everywhere, and I've been searching for this type of jeans for years. The construction is solid with everything.

Thank you for your review! We are thrilled to hear that you have finally found the old school denim you've been searching for. Our goal is to provide high-quality, solid construction denim that stands the test of time. We appreciate your support and hope you continue to enjoy The Pen Slim - Indigo Raw 17.5oz Mammoth Selvedge.
-Kato Team

Ron Elliot
Unlike any other blue jeans

I love these jeans, they look great on me, the look and feel is what I was going for and they did not disappoint. One thing to note the crotch area is a bit snug for me. I highly recommend!

Thank you so much for taking the time to leave us such a positive review. We are thrilled to hear that you love the unique look and feel of our Indigo Raw 17.5oz Mammoth Selvedge jeans. We apologize for any snugness in the crotch area, but we are glad overall you are happy with your purchase. Your recommendation means a lot to us.
-Kato Team

Another banger!

Knocked out the park with the heavy denim. Tailored to my inseam and ready for rocking with my favorite boots.

Absolute best jeans I own

I have an unhealthy amount of jeans from Kato, and this is by far my absolute favorite raw pair. I have never had a heavyweight pair of jeans that felt so smooth and soft to the touch, and yet are clearly very substantial denim. The Pen Slim cut is perfect as usual, but this denim is really world class. I also expected it to be really hot, but it is fine even in the Texas heat. Out of dozens of pairs of jeans, these are my usual first pick.

Thanks for the great review, Pat! We're glad you're happy with the Pen Slim - Indigo Raw 17.5oz Mammoth.
-Kato Team

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Please note that all sale items are not eligible for returns or exchanges.

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