I've used the Carex cane tips for about 3 years now, and my mother used them for several years before that. The product is of good appearance and historically quite durable, lasting months between replacements. The last five tips I've used have lasted only a couple of weeks each before throwing the metal insert then breaking through so that the metal of my cane is in contact with whatever surface I'm walking on. An additional difficulty is that there is no way to predict the event. I've tried checking the tread to no avail. Twice the tip is still gripping smooth surfaces like a suction cup when I leave the house and completely gone before I get home that same day.
This is not acceptable! I'm going to have to find a different solution.