That stabil I believe has a 6 month shelf life of 6 months once opened, the sea foam works for 2 years and is the best product to run through anything that has set for years without running, it saves from pulling the carbs on the motorcycles I pick up, I have a bike in the garage that I just picked up that was sitting since 2012 I ran a half gallon of gas through it with sea foam and it just idles now like it did 45 years ago, I'm no mechanic and this stuff has bailed me out of a few issues and saved me a lot of cash, an old mechanic turned me on to it years ago when I had issues with an inspection on my pick up, works for me anyway...