in a device for adjusting the clearance between a brake shoe and a brake drum of the type having the brake shoes biased against the ends of a strut , the length of the strut being adjustable by the threaded interaction of a nut and a bolt actuated by a star wheel , the star wheel being advanced to lengthen the strut by the parking brake mechanism , a detent for restraining the reverse rotating of the star wheel . in one embodiment , a resilient arm member , fixed to a portion of the strut , acts as a detent against the teeth of the star wheel . in another embodiment , a spring , biasing the brake shoes against the ends of the strut , has a portion engaging the teeth of the star wheel .