Seiko SQ100] inherited this piece from my granddad about a year ago. I wear it with absolute pride but I've come to realise I don't know much about it. When was it
Seiko - Royal Oak Model Sq 100 - 5Y23-8210 - Men - - Catawiki
Seiko SQ100 Quartz Vintage Men's Watch NOS - Etsy
Near NOS 1982 Seiko SQ100 Quartz 6923-7010 – KibbleWatches
Seiko Kinetic sq100 for $285 for sale from a Private Seller on Chrono24