The Seachoice Roller Shaft with Pal Nuts (5/8" O.D. for 8" Rollers) is a sturdy, dependable hardware solution designed to mount and support a standard 8-inch keel or spool roller on your boat trailer. Constructed from high-strength steel with a premium zinc plating, this heavy-duty shaft is built to withstand the highly corrosive effects of harsh marine and saltwater environments. The 5/8-inch outer diameter ensures a perfect, low-friction fit through your roller’s core, while the inclusion of two secure pal nuts provides a quick, reliable, and vibration-resistant installation that keeps your trailer rollers spinning smoothly during boat launches and recoveries.