All-plastic watch movement from the 70s

Here's an in-depth look at Tissot's "Synthetic" watches, the first analog watch-movements made (almost) entirely from plastic. They're quite striking -- some even included calendars.

The escapement is a conventional in-line Swiss lever type, but with all parts made from plastic, excepting the impulse pin. This is synthetic ruby, and is the one-and-only jewel the movement contains. The balance is provided with shock protection. Tissot designed a special shock protection device for this watch. It is similar to the Incabloc system, but the balance pivot runs in a 1-piece molded bushing. This is centered in a conical metal carrier by a 3 armed spring, visible on the top of the bearing.

Link (via Watchismo)