I suggest not using gasket sent, I installed it. Used sealant on both sides of gasket installed it. Put everything back in had two leaks. Thering on tube broke and gasket leaked. Put in green rubber o-ring. Stronger overall, used white grease all over no issues. Used silicone sealant for water pumps thru out gasket. Let set up for 24 hours re-filled with antifreeze no leaks so far all good. Hope it helps.