Wilwood Fittings for adapting Wilwood Compact Master Cylinders. 220-13130 fitting is designed for use with Compact Master Cylinders with 11/16-20 inlet thread and will adapt to -3 AN male fitting used in most AN stainless brake lines assemblies. 220-12943 fitting is designed for use with Compact Master Cylinders with 11/16-20 inlet thread and will adapt to 9/16-18 male fitting which will allow Wilwood Billet Reservoir to mount direct to Compact Master.