On the motor yacht M/Y “Positron”, comprehensive sealing work was carried out on all of the vessel’s portholes, with the objective of restoring watertight integrity and protecting the interior against potential water ingress. The process included inspection and preparation of the application areas, followed by the careful use of suitable marine sealing materials around each porthole. Particular attention was given to uniform application and clean finishing, helping ensure reliable performance in demanding marine conditions. The project was completed at Atlas Shipyards, Greece.