liked when i got in 2011 now three shot called 2-11-2015 for warranty out of business offered refund! only want to give me 60% back about 75 bucks. will have about 26 in shipping! pro rated cause i used for 4 years. i told them wrong lifetime means a lifetime not one thing about pro rated on commercial or warranty! they are screwing everyone i said, also told them i hope an attorney bought a set and i'd be part of the class action law suit! what is the world coming to!! crazy thing is wal mart and others still selling!!