Seikonaut Watch Case - 38mm [ULTRA THIN EDITION / TITANIUM]

Featherlight Strength. Ultra Thin. Titanium Precision.

Meet the Ultra Thin Edition in Titanium—the lightest and most advanced version of the Seikonaut Watch Case to date. Combining the same ultra-slim profile with aerospace-grade strength, this case is made entirely from Grade 4 Titanium—known for its superior hardness, corrosion resistance, and lightweight feel.

While the bezel remains a sleek 38mm, the full case width extends to 42mm with side flanks, and 44mm with the included 7mm coin-edge crown. It wears bold, refined, and comfortably balanced on any wrist size—a true modern classic in featherlight form.

At just 10.0mm thick (with solid caseback), this case achieves an exceptional slimness for an NH-powered build. With a weight of only 29 grams, it’s over 40% lighter than its 316L stainless steel counterpart (49.4g)—a dramatic reduction in wrist fatigue without sacrificing strength or style.

Grade 4 Titanium is the strongest of the commercially pure titanium grades, and notably harder than 316L stainless steel. It resists scratches, dents, and corrosion while retaining the ability to be polished to a sleek finish—making it ideal for everyday wear and rugged builds alike.

Titanium carries a slightly darker, greyish hue compared to stainless steel. While visually subtle, this difference becomes noticeable only in side-by-side comparisons—as shown in the photo. On the wrist, it remains sleek and effortlessly refined.

This edition comes standard with:
• Solid Titanium Caseback (no sapphire display caseback)
• Pre-installed 7mm Coin-Edge Crown (also in titanium)

Included in the package is a flat double-sided AR-coated sapphire crystal. Compatible with all of our 28.5mm dials, SKX013 chapter rings, and original Type M NH-series movements.

Best paired with the Seikonaut Titanium Bracelet for a full titanium build that’s sleek, strong, and featherlight.