I toss them. I don't have any shaving products in my active rotation that I use so seldom that I keep them in the box. The exceptions are bulk razor blades (I still have 8 or nine packs of Derby blades in the box), and the stuff I haven't started using yet (e.g. I have a CO Bigelow shave cream tube that is still in the box because I got two for one on sale).
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