Renis is another example of a Swiss watch company killed off by the Seiko-initiated 1970’s Quartz Crisis - luckily, before it went bankrupt it made a series of well-designed watches, like this 1967 Renis Super Compressor automatic dive watch, on an oyster-style stainless-steel dive bracelet.
 
With the encroaching Quartz Crisis rendering mechanical watches nearly entirely moot, Renis went bankrupt, ending yet another Swiss watch manufacturer.  What was left of Renis was bought and absorbed by Tissot, now owned by the Swatch Group.
 
But this is no plastic hype beast unserviceable watch here - strongly reminiscent of other, similar purpose-built dive watches of the same era, Renis is largely a mystery, mostly lost to the time before the interwebs. It was sold mainly in Europe, with limited distribution.
 
Couple this with an olive-drab green canvas strap and you have an excellent vintage military-esque dive watch, which bears a strong semblance to many much higher priced Super Compressor dive watch offerings of the same era.  In fact, Super Compressors were issued by several navies throughout the world, to include the Royal Australian Navy and Polish Navy.
 
Originally invented in the 1950s by Ervin Piquerez S.A., the term “Super Compressor” is often misused - most people associate the term with any watch that has dual crowns and an internal rotating bezel, but it’s not that simple.  Super Compressor – a trademarked name for specific case designs made by the case manufacturer Ervin Piquerez S.A. (EPSA) – it features patented case sealing method that becomes increasingly watertight the deeper the watch goes via increased pressure application to the case-back, pressing it against the O-ring gasket.
 
Per Worn & Wound, “Super Compressor divers have, for the most part, easily recognizable features that distinguish them as SC cases.  Most, but not all of the SC watches have the distinctive cross-hatching marks on the crowns, and some brands put their respective logos over the cross-hatching.  The crowns are typically oversized and thick, making it easier to operate them under water…”
 
“Another identifying mark is the use of the classic Super Compressor helmet logo.  These were almost always stamped at least on the inside of the caseback, and many brands incorporated a more detailed version of the logo on the outside of the case-back. This is a very cool and easily recognizable feature that immediately identifies a watch as a Super Compressor…These are of course insanely rare and expensive these days…Collecting Super Compressors is a challenging but rewarding endeavor.”  All features present on the Renis Super Compressor here, down to the helmet logo engraved on the inside of the caseback.
 
The so-called Quartz Crisis was a revolution in the watchmaking industry caused by the Seiko advent and successful marketing of the quartz watch, initiated by Seiko with its debut of the Seiko Astron in December 1969.  Heretofore, Swiss watches had claimed the mantle of the world’s most accurate timepieces, and largely ignored new innovations by Seiko – until the Japanese watch manufacturer’s new quartz watches put Swiss watches to shame, accuracy-wise. 
 
Quartz would largely replace mechanical watches throughout the world, and caused significant decline within the Swiss watchmaking industry (hence the moniker, Quartz Crisis); the Swiss chose – stubbornly – to remain focused on traditional mechanical watches, while the majority of the world's watch production shifted to Japanese companies such as Seiko, Citizen, and Casio, which embraced the new technology.
 
This Renis Super Compressor diver comes on a stainless-steel bracelet, and with nylon strap, rugged travel case, and springbar tool.