Car pulls to right

Hi. Recently I purchased a 1999 jeep grand cherokee laredo that pulls to the right, not as noticeable when just driving in town as it is on long stretches of highway over 50 mph. Recently had new tires put on a couple months ago and have had brake work done but still it pulls to right. While in sacto I took it to be aligned and they showed me the rear axle while car was up in the air. They are saying that a plate in the area where the axle goes into the wheel area is what is bent and that if that plate was replaced then it could be aligned and it would be okay. From what I could see, there is a plate that is behind a round area and it is attached with screws. Do u know what this plate is referred to as?