Guy in the video says he is using "lacquer" which could be any number of finishes. Originally "lacquer" was a finish derived from the resinous secretions of the Lac bug from India
. Nitrocellulose lacquers replaced them at the dawn of modern chemistry. More recently there are any number of finishes refered to as "lacquers" that are related to neither.
Regardless, lacquers in general are not preferred for marine
applications but rather "spar varnishes" tend to be the finish of choice on boats, be they older oil
based products or the newer water
based products. These varnishes are distinguished from other similar urethane finishes by the inclusion of UV inhibitors which resist the degrading effects of the sun.
Rotten stone is very old school
, I can't think if the last time I heard it mentioned, and only in the context of fine furniture finishes. 3M makes a products called "Finesse it" and "Perfect it" which are modern alternatives used with high speed buffing wheels widely used in industry.
I think the best take away from the video is the part about sanding
the surface flat, that's the key to a great looking finish. Proper prep and a good gloss varnish
will go a long way to getting a candy coating. Buffing is not an absolute requirement.