Seiko A826 - Christopher Lloyd - Back to the Future
The watch has a unique rotating bezel that activates the different modes. It has an adjustable velcro strap with Seiko-signed buckle. The most unique feature is the the remote finger trigger, used for setting split times, which can clearly be seen in the screenshot.
The Seiko A826 Training Timer is sometimes offered on eBay.
Thanks to Dell Deaton and George Papay