Anti-Gravity Hats

Anti-Gravity Hats were a product sold at Weasley's Wizard Wheezes in Diagon Alley. A slogan written on the package read "Ruin a gentlemans day by making his hat fly away!", so, presumbly, the hats are supposed to be used as a prank. The Anti-Gravity Hat trick has been around for generations in the Wizarding world, and they are not to be used on Muggles.

Appearances

 * Harry Potter and the Half-Blood Prince (film)