This weld-in kit is made of 1-5/8 x .134" wall mild steel tubing. It includes a pair of cage sides, and windshield brace. This kit will convert your existing roll bar to a roll cage. Rocker tubes, dash bar, and side bars are optionally available. Designed to fit hardtop or sedan cars, and trucks listed. Fits most cars with the stock interior installed. It does not go through the dash making the installation easier. They are not designed to fit convertible cars. In most cases the top will not function and the rear bars will need to be placed where the top folds in. Customer is responsible for any necessary modifications if purchased for a convertible car. If conversion kit is installed with a Chassisworks roll bar, your cage meets current NHRA requirements for cars with a 1/4 mile et of 8.50 or more. Includes drawing and instructions. OPTIONAL COMPONENTS IN BLUE