We start out with our 12" balloons to B2P together. Who's will pop first? This is by far the most stubborn balloon I've ever blown to pop. I start slowly blowing up the balloon. My air fills the black balloon. I feel this should be a pretty easy blow to pop. Unfortunately, I was terribly wrong. This balloon that is only 12" has expanded to the max. It appears this black balloon might withstand the pop test. It looks like it could pop, at any moment! The struggle to pop this balloon is really scary!