Over the years, Diesel Kiki has delivered compressors with many different connector styles (see image on right).  The majority use an interchangeable manifold to adapt a common compressor body to the wide variety of fitting types.  In a few compressors, the entire rear cap is replaced with one that uses connectors which are "molded in place". 

With the switch to R-134a refrigerants has come a reduction in the available connection choices.  The new Diesel Kiki compressors are only available with "O-Ring" connectors (shown below).

The high-pressure (discharge) side uses a 1/2" O-ring while the low-pressure (suction) side uses a  5/8" O-ring.  These fittings are available on RParts custom-made refrigerant hoses.
 

CAUTION - If you are converting an R-12 system to R-134a, your old R-12 hoses may not be be compatible.  R-134a hoses are different from those intended for R-12 applications.  Use of incompatible hose will result in rapid loss of refrigerant and may permanently damage your system.  If you have recently purchased your hose, it may be compatible with both.  If you are unsure, consider ordering affordable,  high quality, custom-made R-134a hoses from Rparts,

With the introduction of R-134a there was a concern that automotive A/C technicians would become confused and mix the new (R-134a) and old (R-12) refrigerants.  To prevent this a law was passed making it illegal for compressor manufacturers to sell "automotive" type compressors with 1/4" ports. If they are going to include ports they must (by law) be the of the R-134a "automotive" type.  The photo on the right shows the difference.

One of the easiest ways to put access ports into your system is to use hose connectors that integrate the access ports into them.  Rparts offers your choice of 1/4" flare or R-134a "Automotive" style ports.  When making your selection, remember keep the following items in mind;

The correct hose compressor end connectors are: