This replacement case is for our CRL8300 Series Shallow Depth Floor Mounted Door which is preferred for many types of installations because they only require a shallow 1-9/16" (40 mm) cut-out in the floor. This is especially important on floors above the ground floor. The shallow cut-out leaves enough remaining floor under the Door Closer to support the door weight. The Door Closer has separate valves to control closing and latching speeds. Both 90 degree and 105 degree Hold Open and No Hold Open models are available.