Worn, cracked trailer stops and rollers may cause dings, dents, and scratches on your boat. Prevent costly repairs to both your trailer and boat by inspecting rollers and stops regularly and replacing damaged pieces. We recommend that you use polymer rollers and stops on your trailer. Although neoprene is less expensive, polymer rollers are longer-lasting, contain UV inhibitors, and, unlike some rubber parts, won't leave black streaks along your boat's hull.