These are aftermarket or original equipment manufacturer (OEM) accessories designed to facilitate entry and exit from the specified full-size pickup truck model year. They are typically constructed from materials like aluminum, steel, or durable plastics and are mounted along the rocker panels beneath the doors.
Their importance stems from enhancing accessibility, particularly for individuals with limited mobility, and providing a stepping surface to reach the truck bed. Historically, these accessories have evolved from simple steps to more elaborate designs offering aesthetic appeal and protection against road debris.