½ HP Diaphragm Vacuum Pump Air Compressor Oil Less Thomas Emerson SA55ZZHRM-4636. The item “½ HP Diaphragm Vacuum Pump Air Compressor OilLess Thomas Emerson SA55ZZHRM-4636″ is in sale since Saturday, March 24, 2018. This item is in the category “Business & Industrial\Hydraulics, Pneumatics, Pumps & Plumbing\Pumps & Pump Accessories\Vacuum Pumps\Other…