The O-ring gripper is prepared for picking and placing O-rings on the parts. It has two pistons, which are driven independently of each other. The spreading jaws are double acting and the ejecting jaws are single acting. When pressure is applied to the first piston, 6 parallel jaws spread the o-ring. The stroke can be precisely adjusted using the setscrew. After the o-ring is expanded, air is supplied to the second piston. This causes the ejector jaws to press forward and push the o-ring from the spreading jaws onto the part being assembled. It is stretched evenly in a hexagonal shape; this allows the O-ring to be expanded with considerably less deformation. This can be tooled to accommodate all types of rings, the smallest would be the smallest make tooling jaws to fit the inside diameter and the largest is approximately four inch diameter depending on the cross section.