Initially, I just purchased online, but ordered the wrong part. I called and talked to a real person, who helped me order the correct part and offered a reasonably priced return shipping label. That was a welcome change from other recent online purchase interactions.
Brand new Quincy air compressor unloader tower diaphragm, part # 1855. This diaphragm measures about 3-1/8" across and made out of a reinforced rubber. This diaphragm is designed for models 250, 325, 370, 390 and 5120 air compressors that need part # 1855.
Features:
• Qty: 1 # 1855 Diaphragm
• About 3-1/8" across
• Unloader tower diaphragm
• Part # 1855
• Reinforce Rubber