Vintage 1970s Sicura Slide Rule Diver Sports watch

Sicura watches were started in the 60s by Ernest Schneider, who was a pilot who had interest in manufacturing fashion wearable timepieces. Most of the earlier Sicura watches were made for lower range affordable watches that became popular in the europe, French, UK & American region. However, very-very few people would recognise this watches here in this (Asia) region until recently with growing up interest in vintage watches.
The watches come in many variants and interesting designs, well to update and suit fashion industries I guess. But few design were really made for the "more practical & technical people", like divers, chronographs or this one featured here.
Sicura is always related with Breitling. Commercially yes, technically not quite. It is true after 1979 when Breitling firm was closed down, eventually the firm fell to the hand of Ernest Schneider. Ernest had a believe that Breitling brand with 100 years long history in watchmaking still a strong name in watch industries and he proved it right until today, and eventually Sicura brand was discontinued. Although there were some Sicura watches were produced with Breitling precision and quality as well as design after the takeover, but generally those brands are different in terms of movements and built.
Sicura is somehow a very collectible pieces because of its variety, from simple watches, divers, chrono to jumphour.

This little one, is a jumbo size "computer" with slide rule features with rotating bi-directional outer ring and a fixed inner ring. What it computes is something I have to find out later. If you have any info, welcome to share.
The inner-diver bezel is adjustable by rotating the top crown at 2-and-a-half-o'clock.
Manual winding and time adjusts is done by lower crown at 4 o'clock.
Another feature that i like, really like about this watch is the case shape, thick and unusual shape that remind me of this rare Omega chrono bullhead.

I put on this matching nato strap and it wraps confortably around my wrist... another loveable piece.

Little more info here http://www.sometimeago.com/the-smaller-watch-brands-sicura/