Took this guy apart and put it back together. Works great and pumps hard. Perfect for an espresso machine,car washer any thing you need high pressure for. I took it out of a nicer high quality Laboratory recirculating chiller Heater. I can't figure out which it is because as you can see I took one of the pictures through a magnifier and you can see yourself. They put a 5 over another number probably because it was going off market for chillers maybe? That way mo one could request the correct pump unless they went through the manufacturer. That's my guess,anyway it looks like an 8 for sure and a 3 definitely makes sense.
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