Permatex Surface Insensitive Threadlocker, Blue, Automotive Grade: Oil Resistant; Locks Threaded Fasteners Against Vibration Loosening; Uses - Rocker Studs, Bolts On Valve And Cam Covers; Ideal For Fasteners 1/4" To 3/4" (6 To 20 Mm) In Size. Permatex Threadlockers Fixture In Approximately 20 Minutes And Are Fully Cured Within 24 Hours. Permatex, Made For The Professional. Made In U.S.A. Oem Specified & Oil Resistant. Locks Threaded Fasteners Against Vibration Loosening.