Pettit is good brand an the following is not anti-Pettit.
Sounds like System Three varnish. I tried that seeking a harder coating for our cap rails as while getting aboard we often skuff our shoes on the cap rail varnish. Too thin and peeled of prematurely. The build or thickness of the coating is very thin so many coats could be no more than w one coat of traditional varnish.
We tried several different clear coatings from oil to the water based Three Systems and eventially decided the traditional oil based varnish was best. I believe Epaphanes is harder but we like the high oil (Spar) varnish by McCloskey. Flexability at the wood joints on a cap rail is very important to not crack and allow water to get under the coating and go black w mould. The high oil varnish is most flexable. We just recoated our cap rail and it looks wonderful. Really nice to touch too.
North Western Washington State USA