Im selling this box becouse money is tight right now . It is in great condition! has been on the truck less then a year. It is for a CHEVY DURAMAX 04 AND UP LLY. COME WITH EVER THING THAT CAME WITH IT IN THE BOX TO YOUR DOOR. Asking 510.00 OBO New you will pay OVER --- $900.00 40-125 horsepower increase increase gas mileage by 2-3 miles per gallon, and much more... COMPLETE INSTRUCTIONS used IN BOX. WAKE UP THAT DURAMAX YOU WONT BE DISAPPOINTED!!! THIS IS A MUST HAVE IF YOU TOW OR JUST WANT BETTER FUEL mileage WITH YOUR TRUCK. Level 0: Stock Level 1: 40 Horsepower - 100 Foot Pounds of Torque Level 2: 60 Horsepower - 120 Foot Pounds of Torque Level 3: 75 Horsepower - 170 Foot Pounds of Torque Level 4: 90 Horsepower - 200 Foot Pounds of Torque Level 5: 125 Horsepower - 240 Foot Pounds of Torque YOU MUST PAY SHIPING!! Will only ship in the US IT SHOULD NOT BE THAT MUCH. Thanks for looking.