Loctite AA 3491 is a clear, low yellowing, light-cured, universal, acrylic-based instant adhesive, suited to plastics and well suited to ceramics, glass and metals. It has a high, on-demand, curing speed. Depth of cure is 4 mm. Tack free time 15 secs. Fixture time is 12 secs. Shore hardness: D 75. Medium viscosity 1,100 mPas.