Maple Burl Lacquer box

The SEMPRE watchwinder is the first and only watch winding device that will keep virtually any hand-wound mechanical watch with an accessible  crown fully wound when unworn. This  patented design is truly unique in that it replicates the human action of finger winding a watch by rotating the winding crown similarly in a clockwise direction.

The SEMPRE design substitutes a mechanical finger arrangement, called a "collet", which grasps the watch’s crown securely and rotates it.  Several different size collets are provided to fit any watch crown diameter from 3 to 9 millimeters. These collets are custom made of  acetal plastic to prevent scratching or marring of polished watchcase surfaces. The collet  is mounted in a rotating tubular drive shaft, supported by low-torque precision ball bearings.  It is powered by a miniature servomotor coupled to techno-polymer drive gear system fitted with a safety slip clutch. The collet is opened by pushing a spring-loaded plunger at the opposite end of the drive shaft. Releasing the plunger closes the collet, clamping it on the watch crown. 

5.1"H x 9.7"W x 7.8"D