Invincible Marine Keel Roller, 8-Inches by 5/8-Inches, Black Rubber Made using the highest quality components Performance and quality tested The most trusted name in marine accessories and equipment Holds your spare trailer tire 4-3/4-inches up and 4-1/2-inches out away from your trailer frame Adjust to fit trailer tongues up to 3 W and 5 H Allows your boat to roll smoothly on the trailer and spin freely to reduce drag Measures 8-inches by 5/8-inches in size Comes with a 1-year warranty