Extra-Long Cordovan Strap for a Seiko 6145-8000

A 1968 Seiko on an 8.75-inch wrist is a sizing problem with no shelf solution. Vintage Seiko straps were cut for the wrists of the era, most modern straps stop around 8.5 inches, and the ones that go longer are usually thick sports straps that look absurd on a 40-year-old case. This order needed an extra-long strap for a vintage Seiko 6145 that was still a dress strap when it got there.

Build sheet

Watch	1968 Seiko 6145-8000
Leather	Black shell cordovan
Strap length	90/145 mm (3.54 in / 5.71 in) — extra long
Wrist	8.75 in (222 mm)
Buckle width	16 mm (0.63 in)
Buckle	Classic, stainless steel
Spring bar	Quick release
Stitching	Double side, white
Padding	Padded
Tip end	Tapered

Why these choices

90/145 mm is the number that does the work. Most makers stop at 8.5 inches, so an 8.75-inch wrist lands you permanently on the last hole — the strap fits, technically, and looks like it barely does. Cutting the long side to 145 mm puts the buckle back where it belongs, under the wrist, with holes left on either side of the one you use. That is what we mean by extra long: not a longer tail flapping about, but the whole strap re-proportioned.

Shell cordovan is an equine leather, tanned by Shinki Hikaku in Himeji, Japan. It is considerably denser than cowhide and it is famously close to non-creasing — where a calfskin develops fine cracks across the bend behind the case, cordovan rolls into soft waves instead. On a strap this long the leather flexes across more of its length, so a leather that does not crack is worth the money.

The customer asked for a silver-toned double stitch against matte black cordovan, and specified the stitch run down both sides. It is a restrained detail — two fine lines of thread on a black strap — but on a watch this age it reads as considered rather than decorated.

Questions we get about this build

What length is an extra-long strap for a vintage Seiko 6145? It depends on your wrist, not the watch. Measure around the wrist bone: 8.5 inches and up is extra-long territory, and we cut the two sides independently — 90/145 mm here. Send the measurement and we size to it.

Will quick-release bars work on a 1968 case? They fit standard lug holes, and they save you levering a tool against vintage lugs every time you change strap. If your case has drilled lugs or unusually tight clearance, tell us and we will ship regular spring bars instead.

Cut to your wrist at our bench — allow 2–3 weeks to delivery. Start from the black shell cordovan strap, or browse all custom leather watch straps.