Sawyer Permethrin has a shelf life of 10 years if properly stored in a cool, dry location away from direct UV exposure. We would recommend thoroughly shaking the bottle before use, especially if it has been sitting for an extended period of time.
The shelf is about 5yrs but it's good and effective way past 5yrs. Always remember to Shake it up and away ya go... I have about a gallon (plus) and works great as the day I got it. I use about 24-48oz (1-2 bottles) per summer for 3 adults and 2 large dogs.
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