Abstract: The stabilizer assembly is used to position a stepper assembly for an ultrasound probe. The stabilizer includes two spaced apart swivel assemblies, each swivel assembly including clamps at one end thereof locking the stabilizer to a table. Each swivel assembly includes several swivel arms which are connected at three spaced swivel points. One swivel arm is connected to a central assembly consisting of a central housing with two spaced apart ball joints connecting, respectively, to the two swivel assemblies. A linkage arrangement maintains the ball joints in a locked position by virtue of a spring biased push rod. To unlock the ball joints, the spring is compressed by actuation of a trigger, releasing pressure on the linkage assembly which permits the ball joints to move freely.