T-H Marine - #1 Plastic Thru-Hull Supplier in the U.S.A. Our molded Thru-Hull fittings are used by more OEM boat builders than any other brand. All T-H Marine Thru-Hull Fittings are made of the highest quality virgin material to insure consistent size, extra durability and attractive appearance. All materials are UV stabilized to provide longevity. T-H Marine has worked with major hose manufacturers to guarantee that our hose barbs have the exact specifications to fit hose securely so that your installations will be trouble free. STANDARD 90 DEGREE THRU-HULLS - Our standard 90 degree fittings feature a unique finished head and a pass-around nut for easier and more attractive installation, an innovation that T-H Marine developed. Unique 90 degree fittings: DUAL NUT THRU-HULLS (TH-90 / TH-92) - Traditional two nut 90 degree fittings. Allows for variety of mounting thicknesses. May be used where installation must be done from the topside with a traditional nut. SPANER HEAD THRU-HULLS, 3/4" and 111/8" (TH-7590S, TH-1290S) - For those hard to reach applications that may or may not require low clearance. This spaner head thru-hull allows for installation and tightening from the top with a finished head nut.