Patent attributes
An adjustable ab wheel has a main shaft and two wheels mounted on the main shaft. The main shaft has two external threaded sections. Each one of the two external threaded sections has a thread direction opposite to the thread direction of the other one of the two external threaded sections. Each one of the two wheels has a threaded hole axially defined through the wheel and mounted with a respective one of the two external threaded sections. When a user rolls the two wheels forward, the two wheels approach each other and abut against each other. Abutment between the two wheels allows the two wheels to brake themselves, so that the adjustable ab wheel can prevent users from over rolling the two wheels forward and suddenly falling down to the floor.
