Forums › Forums › Gear – The Stuff We Carry › Watches › Seiko 5 fans This topic has 3 replies, 1 voice, and was last updated 11 months ago by admin. Viewing 4 posts - 1 through 4 (of 4 total) Author Posts September 16, 2025 at 10:39 am #17741 adminKeymaster I measure the strap as 18mm. IS that right? will a 19-20mm leather strap fit? I have a tan face military. I saw one with a brown contrasting stitch strap and looking to change out the nylon strap now. thanks, ran December 11, 2025 at 8:17 am #127111 adminKeymaster Hey ran23, i have a seiko 5 with the blue face, and switched out the nylon for a crown&buckle 18mm leather bomber strap and it fit perfectly. December 11, 2025 at 8:17 am #127114 adminKeymaster Just wondering if a size up will still fit in there? will check Crown & Buckle, thanks December 11, 2025 at 8:17 am #127116 adminKeymaster No a 20mm strap will not fit on an SNK. You can force a thin 20mm NATO in there, but it won’t look good. Stick with 18mm. This photo is an SNK809 on an olive green 18mm C&B NATO. [IMG] Author Posts Viewing 4 posts - 1 through 4 (of 4 total) You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In