This paper describes an end-effector for picking small parts with circular holes, e.g. washers and spacers. There are many issues on the automation of bin picking of small metal parts. In such objects, even if a grasping target can be identified, it is a challenging task to pick it up stable. We propose a novel end-effector using wire thrusting mechanism which enables to grasp a part with holes by squeezing from inside of a hole. Then we built the proposed mechanism and performed experiments using actual 21 cylindrical metal parts. We confirmed that the gripping of the metal parts placed on a horizontal plane performed as designed. In addition, we also confirmed that the same degree of gripping was possible when the inclination was unti118 degrees from the horizontal state. Finally, we organized the points to be improved in the future.