Amazing is right! I, for one, think this thing came ? from the future! Okay, so there's this little metal disc inside, right? You grasp it through the outer plastic, click it back and forth a few times, and PRESTO, the liquid inside starts turning into crystals, and the thing gets hot! Two words: Wow. Wee. And it's reusable! So if you've got a sore neck like me, you got yourself an instant heating pad. Or you could use it for sex stuff, whichever. Comes with massage oil and tip booklet.