In the Kassel Hand, the fingers are attached at their bases to four toothed wheels that sit on a common axis.  The wearer operates the mechanisms from the other hand to push the fingers downward into the desired position.  As each wheel turns, it moves against a pawl (locking spring), a flat pivoted lever which catches on the teeth and prevents the wheel from rolling.  The four pawls are mounted on bases that hold the pawls.  The Kassel Hand has two pairs of flat springs bolted between the mounted pawls.  These apply downward pressure to the proximal end of each pawl to keep them from moving too far in either direction.  The artifact has a large Y-shaped main lever connected to the external release switch.  The main lever acts on the four pawls in order to release the toothed wheels and open the fingers.  In the Kassel Hand, this Y-shaped main lever consists of two parts: a vertical shaft that extends from the release trigger on the exterior of the wrist through the interior of the hand’s shell; and a solid triangular plate with a wedge-like thickness that stretches horizontally from the vertical shaft of the main lever to just beneath the proximal ends of the pawls.  The release trigger, once pressed, acts on the vertical shaft of the main lever, which pushes the solid triangular plate forward.  The wedge-like body of the plate moves beneath the ends of all four pawls at once, moving like a shovel to force them upward, creating a controlled seesaw motion of the pawls that removes pressure from the toothed wheels and allows the fingers to move freely again.