When glass boat windshields or portholes need to be cleaned, use any of Premium Boat Care's exceptional glass cleaners, polishes, and protectants. Marine glass and clear marine plastics are used for the windshield, portholes, and shower doors and mirrors below deck. Glass and clear plastics above deck or at water level are prone to water spots and salt etching. Our glass and clear plastic polishes will restore the clarity to glass and clear plastic boat components and quality protectants will maintain their like-new appearance. In addition to hard boat plastics, Premium Boat Care has products to maintain clear vinyl windows and curtains, also known as isinglass or eisenglass.