New R4 A/C Compressor GM New R4 - 6 Groove Clutch 4.25" Diameter, .85" Gauge Line - Metric Threads - 8mm Pin Coil @ 12 O'Clock 1131875 , 1131921 , 1134327 , 1134328 , 1134343 , 1134376 , 12345923 , 155378 , 16000909-101 , 16000909-102 , 16000909