The Hansa (made in Germany) has a clear site glass on top to see refrigerant flow, The lesser expensive one may not have the sight glass.

rbardolov, I recommended a good compressor oil (BVA mineral oil for R12). for other refrigerant blends or 134A, I do not know.

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1993 Mercedes Benz 300D 2.5 205K (ex wife's)
1984 Mercedes Benz 300SD 320K (SOLD)
2004 Mercedes Benz C240 75K
1995 GMC Sierra 2WD 5.7L 188K
1983 Mercedes Benz 300SD 239K (SOLD)
1987 BMW 325i 220K (SOLD FOR SALVAGE)

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