Crab calipers are not unilateral brakes. According to relevant public information, the small crab calipers are located on the left and right sides of the vehicle, and one side can control one wheel brake, which belongs to a bilateral braking device. Crab calipers refer to the front and rear calipers of electric vehicles. For the front and rear calipers of electric vehicles, it is somewhat similar to the pliers of crabs, that is, the front and rear calipers of electric vehicles are called small crabs.