Revealing mistake: When Cameron gets Abel out of the car and starts running towards the boat, you can plainly see that he's not holding Abel, but a doll.
Continuity mistake: When awaiting news from the police station after the drug declaration, Jax throws his cigarette to his right when the camera is behind him. When the camera changes to show his front, he throws his cigarette again. (00:03:25)
Chosen answer: The First 9 wore these, as can be seen on old pictures. They later switched to leather, but Piney just never did.
Friso94