They combine the ease of application of rub in oils but are fortified with resins to give them a bit more durability. Oil varnish blends are an extremely popular wood finish.
Woodworker Com Rockhard Table Top Urethane Varnish
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Various other additives may be found as well such as dyespigments driers or uv inhibitors.
Behlen Rockhard Table Top Urethane Varnish Gloss Quart 4 Pack
Behlen Rockhard Table Top Varnish Satin 32oz Quart Klingspor S
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