A few reasons why you need jeans like these.

The back yoke with a double chain stitch for extra strength

Goatskin leather patch

Raised belt loop

The irregularities of the yarn in the 14.5oz, 3XXX denim

The Universal zipper made in the U.S (Kentucky)

 The top button made of iron which will give a nice corrosion over time

Copper is used for the rivet instead of iron for a more classic look

The selvedge line on the coin pocket

14.5oz unsanforized selvedge denim line

The denim used in the Pioneer series is the 3XXX denim developed by Masayoshi Kobayashi, the founder of the company. This denim offers intense fading properties that will cause the indigo to fade faster over time, resulting in a contrast blue indigo fade. The series comes with different details and various cuts. One of the most popular models from this series, however, is the 3001 model which is medium to low rise jeans with a slim straight cut.

Mr. Kobayashi is one of the few people in the industry who take a precedence on quality and tradition with his top quality materials and proficient Japanese craftsmanship. The Flat Head 3001 is one of the results of his commitment towards maintaining the original denim production with vintage shuttle looms that offer durability and classic feel. This pair of jeans has been modernized in cut but it still includes the details that date back to the 1960s era.

Flathead jeans are prized the world over with denim aficionados. Zimbabwe cotton milled in Japan on old, worn looms that produce a heavy, soft and characteristic irregular weave.

but at Selfedge (US)

info taken from DENIM AND FREIND