Proto Tools, originally called Plomb Tools, was founded in 1907 by Alphonse Plomb and Charles Williams in Los Angeles, California. Originally working as a blacksmith, the company is accredited with creating the first combination wrench in 1933. The company makes and distributes hand tools.
The company has acquired numerous other tool manufacturing companies over the years, including Cragin Tool, P&C Tool, and J.P. Danielson. In 1946, the company was sued for copyright infringement by another tool manufacturer, J.R. Plumb. The company decided to change the name to “Proto”.
Today, Proto Tools is owned by Stanley Black & Decker, who acquired the company in 1984.