FWIW I have the Airmax PS20 (1/3 HP RPP as Rainman stated). The diffusers are PTFE coated tubes in an H configuration. I installed it the spring of 2014 and have had no problems. The only thing I would do different is upgrade to 5/8 tubing to reduce system operating pressure a little. The standard package came with 3/8.

Last edited by Bill D.; 02/16/18 07:24 AM.
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