Japan Blue Jeans J401 Classic Straight Fit 14.8oz
The J401 Classic Straight Fit 14.8oz from Japan Blue Jeans belongs to the CIRCLE line, a collection designed to offer a more ergonomic approach to Japanese denim, thanks in particular to a curved waistband construction that provides improved support and enhanced everyday comfort. Crafted from a robust 14.8oz Japanese selvedge denim, this model combines heritage authenticity, a classic straight silhouette, and the high manufacturing standards of Kojima.
Features
- 100% cotton / 14.8oz
- Japanese selvedge denim made from American Texas cotton
- Sanforized / one wash
- Red selvedge ID
- Classic Straight Fit
- Mid-to-high curved rise
- Ergonomic curved waistband
- Natural leather patch
- YKK zip fly
- Copper button and rivets
- Chain-stitched hems
- Inner leg seam with signature blue stitching
- Made in Japan (Kojima, Okayama)
Description
With the J401 Classic Straight Fit, Japan Blue Jeans offers a timeless straight-leg interpretation within its CIRCLE line, combining modern technical construction with traditional Japanese selvedge denim woven from American Texas cotton. Known for its strong, slightly irregular fibre, this cotton produces a denim that is both durable and full of character, capable of developing rich and contrasted fades over time.
The 14.8oz fabric sits in a mid-heavy weight category, making it ideal for everyday wear. It offers enough structure to maintain a strong silhouette while remaining comfortable from the first wear thanks to its one wash treatment, which stabilizes the fabric and slightly softens its hand without removing its raw character.
A defining feature of the CIRCLE line is its curved waistband, designed to naturally follow the shape of the hips. This construction helps eliminate gaps at the back of the waist and significantly improves comfort when sitting, while also providing better overall stability. It is a core element of Japan Blue’s ergonomic approach in this collection.
The model features a Classic Straight Fit, a timeless straight-leg silhouette defined by a comfortable thigh and a consistent straight line from hip to hem. It delivers a clean, versatile look that works across styles and seasons, making it the most classic expression of the Japan Blue denim lineup.
Finishing details reflect the attention to craftsmanship: red selvedge ID, copper rivets and button, YKK zip fly, reinforced stitching, and signature blue inner leg stitching. Each element is designed to balance durability, functionality, and understated aesthetics.
Made in Kojima, Japan, this model perfectly embodies Japan Blue Jeans’ philosophy: offering authentic, durable, and modern denim designed for everyday wear while developing strong character over time.
Fit & Sizing
- Classic Straight Fit
- Mid-to-high curved rise
- Comfortable thigh
- Straight leg from hip to hem
- Timeless and versatile silhouette
- Enhanced comfort thanks to the curved waistband
- We recommend taking your usual size
Why We Selected It
We selected the J401 Classic Straight Fit for its refined approach to the straight-leg jean, balancing Japanese craftsmanship with modern comfort. Its Japanese selvedge denim made from Texas cotton offers a lively, durable texture, while the ergonomic CIRCLE construction significantly improves everyday wearability. Combined with a timeless straight silhouette, it stands as a reliable everyday staple built to last.
Unlike the rest of the range Circle from Japan Blue, the Classic Straight fits true to size, we recommend going with your usual size.
In the photos, Quentin measures 1m74 for 68kg and wears the size 30.
Do you have any doubts about your size? You can contact us via Instagram or send us an email to this address: information@flaneurs.net
To properly use our size guide, visit this page
| Denim size guide in cm | |||||||||
| 28 | 29 | 30 | 31 | 32 | 33 | 34 | 36 | 38 | |
| Size | 38.5 | 39.5 | 40.5 | 41.5 | 42.5 | 43.5 | 44.5 | 47 | 49 |
| Thighs | 30 | 31 | 32 | 32.5 | 33.5 | 34 | 35 | 35 | 36 |
| Knees | 23 | 23.5 | 24 | 24.5 | 25 | 25.5 | 26 | 27 | 28 |
| Front fork | 26.5 | 27 | 27.5 | 28 | 28.5 | 29 | 30 | 31.5 | 31.5 |
| Rear fork | 38 | 38 | 38.5 | 39 | 39.5 | 40 | 41 | 42.5 | 44.5 |
| Length |
83 | 83 | 83 | 83 | 83 | 83 | 83 | 83 | 83 |
| Opening | 18.5 | 19 | 19.5 | 20 | 20.5 | 21 | 21.5 | 22.5 | 23.5 |
You can find all information regarding deliveries and returns in our dedicated "Delivery and Returns" section.
In the case of a return, you have a 15-day period following the date of receipt of your order to send back, at your expense, the item(s) that do not fit.
We recommend following the instructions on the return slip that you can download by clicking here.
