This double Watch Winder is encased in a beautiful High Gloss Maple Burl case and has a beveled viewing glass and is fully lined with luxurious black suede. Inside are two self-programming winder modules powered by 5 year lithium batteries. The patented Rotorwind system "rocks" the watch in an oscillating mode, once every 10 minutes, 24/7. This gentle action replenishes the mainspring torque. That is the optimum arrangement to insure the highest watch accuracy. Ball bearing construction throughout, coupled with the use of Swiss designed ironless core precision servomotors assures long life with no maintenance ever required. A low battery light automatically signals when battery replacement is needed.