I am installing new portlights (Newfound Metals bronze) that come with unfinished interior teak frames (spacers) that compensate for the relatively thin thickness of the fiberglass house walls. Once the ports are installed, it will be a real pain to refinish the exposed edges of the spacers, so I was aiming at longevity. After considerable research, I chose a solution that is a combination of Epifanes products: 3 coats of Clear Gloss, followed by 3 coats of Matte Finish. I won't know about the longevity for a decade or so, but I am very pleased with the appearance of the matte finish. Even after 3 coats of gloss "foundation," the teak looks and feels like it has no finish at all. So far, so good.