German manufacturer Sinn makes a watch - the UX - which is rated (if I read the specs correctly) to keep time to 5,000m (16,500ft.) and work after being at the

German manufacturer Sinn makes a watch - the UX - which is rated (if I read the specs correctly) to keep time to 5,000m (16,500ft.) and work after being at the bottom of a km-deep bore hole at the bottom of the Mariana Trench - the case is rated for 12,000m/39,500ft).