Postcard I would sniff you first

Imagine you get a totally crazy card. It's so minimalistic that it's almost stylish. And the saying on it? Hold on tight: I'm not saying you're old, but if you were milk, I'd sniff you first. Yes, you heard right! This card is absolutely awesome. It brings the ultimate humor to your message. And as if that wasn't enough, there's also a good old milk bottle depicted. You remember, right? Those bottles that we opened with excitement as children. But seriously, with this card you can...