Retrax 08-up Super Duty F-250-350 Short Bed RetraxPRO MXRetraxPRO MX bed covers are made with heavy duty aluminum slats covered in a matte powder coat, giving them the strength to support distributed loads of more than 500 pounds! The RetraxPRO MX features a limited lifetime warranty, meaning you'll never have to worry about your bed cover once you have it installed. Sealed ball bearing rollers are mounted onto each section. This allows the retractable cover to open and close easily with one hand, without