It’s a brilliant move because the soft, supple leather used for dress shoes is virtually identical to that used for watch straps. The panel sizes required to make two-piece straps also align with the scraps created by shoemakers.

The lining of the leather straps is also sourced from Regal.
Seiko

Regal also provides Seiko with the lining material used for the soft underside of the straps. It is the same fine-grain leather used to line Regal dress shoes.

Unfortunately, Regal no longer carries the matching oxblood penny loafers that inspired the strap.

Shiracha silk

Seiko’s Presage Classic Series features dials inspired by traditional Japanese craftsmanship of the Edo period, which lasted from 1603 to 1868. Much like the Renaissance in Europe, it was a golden age of artistic innovation.

Shiracha is a light brown shade prized during the Bunsei era of the Edo period. It was used in artwork and decorative design for its soothing atmosphere.