1 Bolt to 3 Bolt Cam Gear Conversion Kit for Gen 4 LS Engines Includes: 3 Bolt 4x Cam Gear Replaces 12586481 LS2/LS3/LS7 Style Timing Chain Dampener ARP 3-Bolt LS Cam Bolt Kit 134-1003 This kit allows you to install an aftermarket camshaft in most 2007-2013 GM LS style engines that originally came with single-bolt cams. Includes a fixed chain dampener to replace the failure-prone spring style dampers used on the 2007 and newer engines. No returns on opened products.