These are red rubber,foam layer and a white gel plastic with the stamp pic, this is the part that clings to your blocks. Living in AZ & dry out issues... do you have a/c? If yes try to set up a room that is climate controlled if you can, this is what I do since I have central air, I needed to invest in a tiny a/c to control my art room. Here is another option which I also use, got a tiny refrigerator to store heat sensitive items in as well. Try for the coldest darkest spot in your home 70 degrees is about perfect. You can try to revive your clear cling stamps by soaking in a solution of (distilled) water and add some glycerin added to retain moisture. (I've been able to bring back many this way...not the cracked ones) ALWAYS Store your stamps in an airtight container! I double down on that in this fashion: I Store my stamps in gallon ziplock FREEZER bags, then place in a large tupperware container or a masters portable palette that has an airtight lid. Then I Store my containers in fridge, freezer( don't forget to thaw before using) or my climate control space. I am a Fine Artist, used to live in AZ Sonoran desert area & ALL my supplies were either referidgerated or climate controlled. ''Tis a harsh climate there & this is how everything other than paper or canvasses were stored! I hope you see this & hope it helps you!