Hi Joe

We used to have the shelf-life listed on the bottle as "about one year opened; 3 years unopened".  We have removed this from the labels and have added storage directions.  As long as the glue is in its liquid form, no matter how old it is, it is at full strength and fine to use.

Gorilla Glue is a moisture activated adhesive and there is moisture in the air.  When finished using the glue, you must squeeze the bottle and let the glue go back up into the spout.  When the glue gets to the tip of the nozzle, while holding this squeeze keeping the glue at the tip, replace the cap.  The bottle will be misshapen since you have used the glue to force all of the air out of the container.  The next time you use the glue and remove the cap, the air will rush back in and re-inflate your container so you can get the glue out.  Remember to remove the air after each use. This will keep the glue in its liquid form.

The 2 oz container is recommended for occasional home use.  One drop of Gorilla Glue will foam and expand 3 to 4 times that in volume so only a small amount of glue is needed.

I hope this helps!

MaryEllen