The Vevor boat trailer guide-on set is designed to make loading ski boats, fishing boats, and sailboats easier and more controlled. It features heavy-duty steel brackets with a powder-coated finish for durability and resistance to rust and saltwater exposure. Two 60" PVC tube covers with end caps help protect the boat hull from scratches during loading. The adjustable design fits trailer frames under 3" wide and 4-1/4" tall, and mounting hardware is included for flexible top or bottom installation.