The Casio F-91WB-1AEF is a modern take on the classic F-91 digital watch, featuring a minimalist face design and a one-tone color scheme for a clean aesthetic. The band is constructed from bio-based resin, aiming to reduce environmental impact.

• Case size: 38.2 × 35.2 × 8.5 mm
• Weight: 21 g
• Case and bezel material: Resin
• Band material: Resin (biomass plastic)
• Water resistance: Daily use water resistance
• Approximate battery life: 7 years (CR2016)
• Accuracy: ±30 seconds per month
• 1/100-second stopwatch (60-minute, split time)
• Alarm: Time alarm and hourly time signal
• LED backlight (green)
• Auto calendar
• 12/24 hour format switching