Okay, so I was totally skeptical at first but this tape is LEGIT. Had a nasty leak under my kitchen sink (thanks, old pipes) and this stuff slowed it down to just a tiny drip. Not perfect, but way better than the rubber gutter glue I tried before.
The stickiness is NO JOKE - like 'wear gloves or regret it' level sticky. Tried peeling some off to reposition and... yeah, that's not happening. Permanent is right!
Used it on my RV roof last month too? Silver side facing up? That reflective heat thing actually works? My AC isn't struggling as hard now.
Pro tip: Cut pieces before peeling the backing unless you enjoy wrestling with ultra-sticky tape snakes. Learned that the hard way when 5 feet of tape stuck to itself mid-air like some kind of adhesive cobra.
Only complaint? That one review about concrete pools might be onto something - seems better for smooth surfaces than rough textures. But for $10? Still keeping a roll in every toolbox.