Just like our rear brake calipers we are having original Cores rebuilt by a top-quality company. We did offer these on an exchange basis, but our rebuilder is retiring so we will be unfortunately discontinuing this service. Currently what we have in inventory are the last compressors we will have and once sold this part will be officially discontinued (update morning of 3/19/26 we have just one left). We are now selling these outright with no core charge and once our inventory is completely gone, we will remove this from our site. It is STRONGLY recommended that you replace your receiver dryer, liquid line and condenser when servicing your system...Follow the R134 conversion procedure with proper O-rings and compressor oil when you install. If your old compressor suffered a failure that sent metal through your system then you will have another failure with the replacement compressor.