Westin R5 M-Series Wheel to Wheel Step Nerf Bars Polished Stainless Steel 5 in. Model 28-534330Westin Westin R5 M Series Wheel to Wheel Nerf Bars Polished Stainless Steel 5 in. Model 28 534330 Get a boost, with Westins R5 M Series Wheel To Wheel Nerf Step Bars. The extra wide 5in. footprint step design provides easier and safer vehicle access for both drivers and passengers. Developed and engineered in the USA, the R5 M Series Wheel to Wheel Nerf Step Bars feature three oversized skid resistant step pads allowing easy access to the vehicle cab