Hollowback (marine grade type 304) has concave back to fit rigid vinyl rub rail and provides added protection and chrome-like accent around entire boat. Most widely used stainless steel inserts fit the largest variety of vinyl profiles on the market. Solid back stainless steel rub rail (marine grade type 316) provides premium heavy-duty protection and a polished finish for your boat.TACO # S11-4500P12 Hight : 1/2" Width : .062" Length : 12" . . Screws : #6