The strap size depends on the reference. Yours is engraved on the case back or between the lugs at 6 o'clock.
18 to 21 mm
Verification: From our database, not yet verified
38 to 44 mm cases · 1999 to 2015
Indicative information. Check your watch before buying a strap: whatsmylugwidth.com is not responsible for an incorrect size.
Grand Seiko Spring Drive references in our database. Each card says where its width comes from: listed by the maker (linked to the maker's page in the details), two independent sources agree, or listed in our database and not yet verified by us.
Spring Drive Chronograph Sport
Lug width: 21 mm
Source: DatabaseCase size: 43 mmYear: 2015Black dialCase material: Steel
Spring Drive First Gen
Lug width: 18 mm
Source: DatabaseCase size: 38 mmYear: 1999Silver dialCase material: Steel
Spring Drive GMT Blue
Lug width: 20 mm
Source: DatabaseCase size: 44 mmYear: 2015Blue dialCase material: Steel
No reference matches.
Grand Seiko Spring Drive lug width: 18 to 21 mm depending on the reference. The most common is 18 mm (1 of the 3 references with a listed width in our database). Find your exact reference in the table below. These widths come from our database and are not yet verified.
No. 3 different lug widths appear across the line, often by case size or generation. Check the reference engraved on the case back or between the lugs.
From our database, which lists 3 Grand Seiko Spring Drive references, 3 of them with a listed width. Each reference card says whether the maker lists the width, two independent sources agree on it, or it is not yet verified.
The gap between the two lugs that hold the strap, in millimetres. A new strap must match it exactly: 20 mm lugs take a 20 mm strap.
Most watches use spring bars, so any strap of the right width fits. Many smartwatches use their own band system instead, such as Apple Watch bands or Garmin QuickFit.