The Keystone Watch Case Company, Philadelphia

How a Jas. Boss Watch Case is made

Gold Outside Stiffening Metal Gold Inside

The Jas. Boss Stiffened Gold Watch Case is made of two layers of Solid Gold with a layer of Stiffening Metal between welded and rolled together into one solid sheet of metal. The Jas. Boss Case is a Solid Gold Case for all practical purposes. The Stiffening Metal simply adds strength and durability. The Boss Case is guaranteed for 25 years by the largest watch case makers in the world, who have been making it for a full half century. Every Boss Case has the Keystone trademark stamped inside. Ask any dealer to show you one. Write us for a booklet telling the whole story.

The Keystone Watch Case Company, Philadelphia.

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