The I/O Port Seat Back Brace has met with approval by SCCA, PSCR, NASA, PCA and other sanctioning bodies' scrutineers. These strong steel units are designed to bolt to the back of the seat and clamp to the roll bar, no welding required. Our quick-pin brace adjusts from 2 1/2 inches up to 15 inches making the brace ideal for multi-driver cars. This brace can be used with just about any aluminum or composite seat at any angle. For fore or aft adjustments, just pull a pin, slide the seat and reinstall the pin. For other adjustments the brace can be loosened so that the seat can be tilted or moved up or down and the brace then re-tightened. SCCA, NASA, PCA, and PSCR (IMSA) require such a brace on all seats. For added safety, inside impacts, we reccommend using two of these braces. All mounting hardware included.