A parallel gripper includes a housing and two adjustable gripper base jaws which are displacably guided in a jaw guiding recess. The base jaws are moved relative to one another by a wedge hook gearing that is adjusted by a piston guided in the housing. The jaw guiding recess is provided with complementary configured guiding grooves. The ratio of the wall thickness of the housing between the base of the guiding grooves and the outside of the housing to the width of the housing measured vertically in relation to the direction of displacement of the base jaws is at least 0.2. The ratio of the width of inclined traction of the wedge hook gearing to the outside width of the base jaws is at least 0.4.