Saturday watch here, Casio made some great lines of timepieces, but the calculator watches are probably the most recognized, this one is the Casio CFX-400! Capable of normal timekeeping, it was a
Vintage 1983 Casio 197 Cfx-200 Scientific Calculator Watch Works Great for sale online | eBay
Hands-On: Yes, You Can Still Buy A Casio Calculator Watch - Hodinkee
CASIO (197) CFX-200 SCIENTIFIC CALCULATOR DIGITAL WATCH FOR PARTS & REPAIRS# | eBay