Running boards or nerf bars are tubular devices fitted to the side of a trucks, sport utility vehicles and other similar off-road vehicles to act as a step for easy entry and exit from the vehicle. They are typically constructed from either stainless steel, chrome or powder-coated steel although there are considerable variations in style, color and design. They are also referred to as step bars, boss bars, tube steps or step tubes.

Aside from facilitating easy ingress and egress from a vehicle, running boards also protect the body sides from damages. The stable support provided by a set of nerf bars or running boards is a great measure of safety and peace of mind especially for younger or older passengers. Side steps are built to handle abuse as most are bolt-on to a vehicle in a pre-existing mounting position on the frame.

Supported by the steel construction and heavy-duty frame mount brackets, a standard running board also boasts of an incredible weight capacity as it can hold up to 300lbs. or more at a time. Heavy-duty running boards fitted with an aluminum support frame beneath the stepping surface can even carry a weight capacity of up to 500lbs.

During wet weather, a running boards' treaded pads help passengers get a safe grip on the step before climbing into the vehicle. These all-weather pads have a grooved design that channels water away from the stepping surface. Aside from providing a non-slip surface for stepping, nerf bars also help to keep dirt and mud from reaching a vehicle's carpet. The treaded pad is an excellent place to wipe one's feet, while the tube becomes an ingenious tool for knocking off the mud.