ITW Dykem Cross Check Torque Seal Gray is similar to a wax seal for critical holds and fastenings. Under black/UV light, Cross Check's highly visible marks provide a reliable means for identifying vibratory loosening or tampering in nuts, bolts, fasteners and assemblies. Safe for most surfaces, Cross Check boasts excellent adhesion to metal and other substrates and warranty protection against tampering. Dries to the touch in 30-40 minutes. Total curation occurs in 7-10 days, but may occur faster when exposed to elevated temperatures or hot air.