Walter Schlage patented his first invention in 1909 — a door lock that had the ability to turn the lights on and off. Around 1920, Schlage left his job at Western Electric and opened his own shop. There, he developed tools for manufacturing the first lock with a push-button centered in the knob. In doing so, he advanced the concept of the cylindrical pin-tumbler lock by including a push-button locking mechanism for the first time. In 1923, Schlage moved his company to a new space and began full-scale production of his locks, which helped revolutionize the door industry. After his death, Schlage’s company lived on and began a period of expansion throughout the 1950s and again in the 1970s. In 1974, the company was acquired by Ingersoll Rand and expansion continued — as did the innovations. In 2013, the company became part of Allegion and in 2020, Schlage celebrated its 100-year anniversary. Today, the company remains one of the most well-known lock manufacturers in America and offers improved versions of its famous push-button knobs as well as more sophisticated technologies like WiFi-enabled smart locks and innovative house locks that sync with your Apple Watch so that no key is required.