C-Hinge

Our new and unique C-Hinge technology provides that snap we all love in a new pair of sunglasses

Don't you hate it when after a few months of wearing sunglasses, the hinges lose their "snap", they become loose and flap around. This happens to almost all sunglasses, cheap or expensive.
 
Thankfully flappy arms are now a thing of the past with the Panda C-Hinge.
The arm is constantly held under tension from the C shaped metal, this means they are not simply relying on screws to pivot around.