Shipshape 9" Rubber Roller Boat Guide - Ons won"t mark your boat. Makes boat loading easier. Heavy-duty, hot-dipped galvanized steel construction with non-marking 9" rubber roller and end caps already assembled; Height approximately 20" with side adjustment out to 13"; Extra mounting for up to 4 1/4" trailer frames included; Come as a pair. Order Today! Shipshape 9" Rubber Roller Boat Guide-Ons