These are genuine TRW calipers and each item is one side of the caliper complete with piston. 4 Front halves are needed per car. International Buyers – Please Note. These charges are the. Please check with your. Or your country’s. To determine what these additional costs will be. These costs can range from none to over 40% of the value of the item. It is totally out of our control. We will not know anything not shown in the tracking. We have no control over lack of tracking detail.