Stern eyes are constructed of corrosion resistant machined 304 stainless steel and come with adjustable finish nuts which provide superior performance over crimp ring style stern eyes. For use as a tie-down point on your boat?s stern. Robust backing plate for added rigidity in water ski tow applications. A 1/2" NC B 3-1/2" C 1-3/8" D 5-5/16" E 1-7/8"