survan swiss automatic watch for men sapphire crystal mechanical skeleton wrist watch 18k yellow gold ion-plated leather strap silver survan watchdesigner <br><br><b>specifications</b><br>crystal:sapphire<br>case material:stainless steel<br>band material:genuine leather<br>band width:22.00mm<br>case diameter:44.00mm<br>water resistance depth:100m <br><br><b>automatic watches</b><br> automatic watches do not operate on batteries. automatic watches are made up of about 130 or more parts that work together to tell time. automatic movements also referred to as self-winding, watches with automatic movements utilize kinetic energy, the swinging of your arm, to provide energy to an oscillating rotor to keep the watch ticking. they're considered more satisfying to watch collectors (horologists) because of the engineering artistry that goes into the hundreds of parts that make up the movement. if you do not wear an automatic watch consistently (for about 8 to 12 hours a day), you can keep the watch powered with hand-winding.