The second model is a wolf in sheep's clothing: the stainless steel watch on the TV screen looks like an ordinary mechanical watch with a date. The second hand flows at 28,800 A / h over the silver brushed dial. Only the bottom glass reveals which specialty has been installed here: The ESA 9154 Dynotron. The movement was only built for a few years - from 1970 to 1975 - and is one of the few movements in which the balance wheel is powered by electricity. The balance has 2 magnets, underneath there are 2 coils. The control coil generates an electrical pulse when the balance wheel passes a certain reference point. A transistor amplifies the pulse and acts on the driver coil. This is how the balance wheel deflectsreplica rolex watch perfect yacht master 169622 35mm black dial a reversal of the usual principle of an lever escapement.