My grandfather's Seiko RC-4000 watch from 1985. The "most advanced, hight tech" watch for its time that connected to the Apple II computer. : r/BuyItForLife
Before Smartwatches, There was the Seiko UC-2000 Wrist Computer, Here are 5 Cool Facts - TechEBlog
Seiko Quartz Diving Computer Digital Men's Watch STN009J1 – Chronobuy
SEIKO WATCH | Our Heritage
Buy NIB Vintage 1983 NOS SEIKO UC2000 complette LCD wrist computer system pocket set Online at Lowest Price in Ubuy Poland. 264538730810
Seiko Wrist Module Uc-2000/seiko Wrist Information System - Etsy
The origin of 'wearable computer' was in Japan in the 1980's - GIGAZINE
Seiko Computer Watch Fun | Vintage Electronics Have Soul – The Pocket Calculator Show Website
SEIKO UC-2000 / 2100 With Keyboard Fantastic NOS Rare | eBay
Show Us Your Most Geeky/Unusual Seiko or Citizen | WatchUSeek Watch Forums