For you younger tradesfolk who have entered into a mechanical career within the past 20 years, you may never have encountered PB (polybutylene) tubing and fittings. To tell you the truth, it’s been a long time since the PB product recall, and more than a decade or two since I have had to deal with PB installations. They say things come in threes and that certainly was true for PB and me over the past month!