Hermle Mechanical 122 mm Brass Serpentine Hand watch mainspring winder Crystals need to be thin

Crystals need to be thin to allow the cover (lid) to close on these styles of watches

007" thick

The 10 mm replacement pusher (driving punch) should be slightly larger than the outside diameter of the Bushing

This American lathe chuck has an opening of 8

Venus®210

Hermle Mechanical 122 mm Brass Serpentine Hand watch mainspring winder Crystals need to be thinHermle Mechanical 122 mm Brass Serpentine Hand an FHS brass serpentine clock hand. Fits the majority of Hermle mechanical movements with the exception of models 471, and 1171. Minute hand has a square hole 2. 5 mm x 2. 5 mm with a length of 122 mm. Hour hand has a round hole diameter 4. 5 mm with a length of 87 mm.