When it was introduced in 1963, the Seiko Sportsmatic 5 heralded multiple innovations: The first was the Diaflex mainspring, Seiko’s unbreakable mainspring. Another was the Dias ...

There is a remarkably similar Silverwave that Seiko produced under the 5 Actus line later in the 1970s. This one has a funky textured dial and can typically be had for less than $200. But from ...