These besides are designed for trucks with serious off road suspension and large off road tires. They provide 8" of additional tire coverage per side. Larger tires are recommended to fill the wheel well gaps. Part # TU-B-12 Features include: - 8" Wider bulge - 2" larger wheel well opening  - Will accept a 37" tire  - Dove tailed ends for increased departure angle  - Additional interior space for 4-link suspension set ups.  - Retention of factory taillights and tailgate Required Modifications for Install: - Wheel well supports will need to be modified for new larger and wider bedsides (parts not included) Prices are for the Pair   offroad fiberglass