Tonno Pro 42-199 Utility Track Installation Bracket Kit for Tonno Fold or Hard Fold for 07-15 GM Silverado/Sierra Utility Track Installation Bracket Kit for Tonno Fold or Hard Fold for 07-15 GM Silverado/Sierra Use this adaptor bracket kit if you have the GM Utility Tracks installed on your truck bed. This allows the Tonno Pro Tonno Fold or Hard Fold Tri-folding Cover to to be easily installed.