Compatible with 1962-1967 Chevy® II. This product is not created or sold by GM®.; Replaces the stock rear rails in subframe equipped cars. Engineered to move the leaf springs and frame rails inboard to provide additional tire clearance. Designed to fit stock floor contours with minor fabrication. Requires use of a fuel cell, Rear Fenderwells and an Upper Shock Crossmember. Eliminates stock sheet metal rear frame rails. Increases chassis strength for quicker vehicle reaction times. Use with Competition Engineering Weld-in Subframe Connectors No. C3014. Manufactured from mandrel formed 2" x 3" x .083" wall mild steel tube. Two rails and tube sleeves.;.