This is a shock bracket that converts the upper rear shock mount on the 2010-2015 Camaro from a stud/post design to a bearing/coil-over mount style. The mount bolts into the factory location so no modification is necessary.  A shorter shock may be required when using this mount. To determine the correct length of shock, establish your desired ride height for your vehicle. Then, measure from center of upper mount to center of lower mount to determine the proper shock length.