Schlage (/ʃleɪɡ/ SHLAYG) is an American lock manufacturer founded in 1920 by Walter Schlage. Schlage was headquartered in San Francisco from its inception until it relocated to Colorado Springs, Colorado, in 1997. Schlage also produces high-security key and cylinder lines Primus, Everest, and Everest Primus XP. Schlage is one of the most popular brands of consumer and commercial locks in the United States.