Vintage Delaware 17 Jewel Incabloc Unbreakable Mainspring 。Brand: Delaware Movement: 17 Jewel Mechanical Feature: Incabloc shock protection. Incabloc is a system used to protect the delicate balance wheel and its pivots from damage due to shocks. Inscription: \"Unbreakable Mainspring\" suggests a durable design. Origin: Likely made in Germany, as Laco (the manufacturer of Delaware watches) is a German company founded in 1925. Era: The style and features suggest it is a vintage piece, possibly from the mid-20th century. Durability: Laco watches are known for being robust and reliable.