A digital wristwatch for your finger — practical and playful. Compact design, sophisticated look, and a touch of pure fun.

Creating a ring-sized version of the Casio watch’s complex form and functions was no easy feat. To make this possible, we needed to use advanced metal injection molding (MIM) to recreate fine details with precision in stainless steel. The ring is then finished with gold-colored ion-plating for a polished gleam.

The monocoque case and special glass adhesive technique ensure a tight seal for everyday water resistance, while still allowing the battery to be replaced. We downsized the standard watch module by a factor of 10 and paired it with a small button battery to create a fully functional 3-button digital watch that actually fits right on your finger.

Even at this small size, the watch features a 7-segment LCD that shows all the info you need — hours, minutes, and seconds, as well as date, dual time, and stopwatch. A soft, flashing light activates at your chosen time, offering a subtle and emotive glow.

The ring fits a size 22 finger (US 10.5, EU U) and comes with two size-adjusting spacers, in size 19 (19-mm inner diameter) and size 16 (18-mm inner diameter).

• Case / bezel material: Stainless steel
  
• Gold ion plated case
  
• Mineral Glass
  
• Water Resistant
  
• LED backlight
  
• May not be visible in bright light.
  
• LED:White
  
• Alarm/hourly time signal
  
• Time flash (daily and every hour on the hour)
  * The Time Flash light may not be visible when ambient lighting is bright.
  * Time Flash is intended for entertainment purposes.
  
• Dual time
  
• Auto-calendar (28 days for February)
  
• 12/24-hour format
  
• Regular timekeeping:
  
• Digital: Hour, minute, second, pm, month, date, day
  
• Accuracy: ±30 seconds per month
  
• Approx. battery life: 2 years on SR621SW
  
• Size of case : 25.2 × 19.5 × 6.2 mm
  
• Total weight : 16 g