Instruct: Classify Amazon reviews into positive or negative sentiment
Query: questionable durability

The product was shipped quickly and intact. I bought the crutch tips on behalf of my uncle who frequently uses crutches. It appears that the 1st & current pair of new crutch tips he is using are wearing out rather quickly. Now to be fair, my uncle-the user of the tips, is not exactly a lightweight thus a possible?? cause of the premature wear on the crutch tips. I really can't say but we are a lil disappointed as a more sturdy tip was hoped for.