Is TotalBoat Halcyon a water-based polyurethane? Eric Boudreau November 25, 2020 19:47 Updated TotalBoat Halcyon varnish is a water-based polyurethane coating which was designed for superior performance, making it suitable for marine applications. Related articles Can I apply TotalBoat Halcyon over an oil-based stain? Will TotalBoat TotalStrip remove TotalBoat Halcyon? Can TotalBoat Halcyon be applied over TotalBoat Wood Sealer? Can TotalBoat Halcyon be applied over linseed oil or tung oil? Which varnish should I use? Comments 0 comments Please sign in to leave a comment.