ACR ResQLink+ PLB, purchased new in 2014.  Always kept clean/dry; never activated.  Test mode shows that it still works fine, but is beyond its recommended 5-year battery replacement.  I no longer use this, so doesn’t make sense for me to do the battery replacement (which costs about $135 and includes a 5-year certification).  ACR makes what are arguably the most bombproof, reliable PLB out there.  It’s yours for just the shipping cost (estimated $8-10). Comparable current model costs over $300, so this is a great deal.