Defiantly can be mate. Some of these kits I have had for a couple of years. They are still perfect. Aslong as they are stored in a cool try place. Stored flat is best. But if you cant stored rolled up in a large diameter is best. (about 200-300mm). Just need to be kept cool and obviously dry and out of sunlight. (not that the colours will fade in the sun as they are screen printed) but you don't want the sun to effect the glue.
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