we get ours from ace hardware. we used to get red devil which was 100% lye,now we get the ace brand because red devil went out of business but yes im positive,it says 100% lye right on the bottle...
sodium hydroxide is the chemical name. yes you can get pure lye crystals at almost any ace hardware. dont get the shit on your skin though, i spilled some once, and it got on my foot, and my foot swelled little bumps that burned and itched for like a week.