I have tubeless tires on my MTB. Before I started using Slime, it was horrible because the tubeless tire, once repaired after a flat, would not inflate unless a powerful compressor was used. I ended up calling my bike's "roadside assistance" (my wife to pick me up, that is). Now with Slime, I just see green dots where punctures are. Air escapes a little, taking with it some Slime, then sealing the opening. I haven't had much luck with Slime and 700x23C road tire though. I now use Armadillos with Lunar Light tubes. No flat & cuts yet after 231 miles.