Casio Retro Vintage B640

The B640 extends the Casio retro stainless steel format into data-bank territory, adding a telephone number memory and schedule keeper to the same rectangular case language that defines the vintage digital series. In an era when a dedicated data-bank watch represented genuine utility, the B640 was a practical instrument; today it occupies an interesting position within the Casio Retro Vintage family as a piece that carries both aesthetic and functional history. The integrated stainless steel bracelet, the quartz movement, and the digital display align it visually with the A158 and A168, while the multi-function module gives it a different kind of usefulness. Water resistance is rated at 30 metres, covering everyday conditions with appropriate margin. The mineral crystal sits flush within the bezel; the differences between crystal types — and what they mean for daily wear — are explained in the Watchello guide to watch crystals. For those mapping the full scope of Casio's catalogue through Watchello, the B640 is a useful marker of how the brand approached utility design before the smartphone made dedicated data-bank devices redundant. The watchmaking glossary covers the terminology relevant to this category. Watchello ships every B640 reference internationally with full warranty documentation.