This is a pair of large and small Tube-O crimp-on fittings for the Sanden 508 compressor needed for adding a Sanden 508 a/c compressor. The fittings have female # 8 3/4"-16 for the discharge and female # 10 7/8"-14 for the suction side. Includes proper size viton o-rings. These also fit our billet fitting adapter we machine for the SD7B10 compressors.