An unopened tube of GEAR AID adhesive including Seam Grip WP, Aquaseal FD and Aquaseal SR, has a four-year shelf life. The “born-on” date is crimped into the bottom of the tube. The adhesive will be good for four years or longer past that date. As long as you can draw adhesive from the tube, it is good to go. Once you puncture the tube and expose the adhesive to the moisture in the air, the curing process begins. You are unable to stop this process, but you can slow down curing by storing the adhesive in a dry environment.
An opened tube of adhesive will probably last 3-6 months longer depending on storage.