2 year guarantee. The URO did not reply to my letters. I think they're just a crappy company selling cheap junk. I won't buy anything from them anymore! My friend had the same problem and he said just go to Granger and buy a 42 x 2mm o-ring because you can choose whatever material you want and they are only about $0.80 each. Hello URO: β¦. "Raise yours"