Antique 10 Size Keystone J. Boss Pocket Watch Case for Mechanical 14k GF USA. Item: Pocket Watch Case Brand: Keystone Model: J. Boss Movement: Mechanical Case Material: 14k GF Country: USA Gender: Men’s. Inside Diameter: 40mmmm Outside Diameter: 43mmmm. Ok, overall condition for its age. There are dents and scratches on the case. There are scratches on the crystal. It is missing the stem and crown.