The very best and most expensive watches in the world have mechanical in-house movements. That is, theyíre wind up / spring powered, not battery powered like a modern quartz watch, and all those springs, cogs and gears are made by the same company that puts the movement into the watch case. Just like my Russian Vostok Komadirskie. Not that the Vostok particularly good. Itís erratic, sometimes running a bit fast, or a bit slow. And occasionally it just stops; especially if I forget to wind it in the morning! Good thing it wasn't expensive then! But it is fun though and I love the sweep second hand. It divides each second into six tiny movements rather than that dull second by second tick tick of a quartz. Itís been running quite well for the last few days and so has been given some wrist time and a new strap.