Time-Sert 0561 5/16-18 Inch Thread Repair Kit has a provided insert length of .450 inches Time Sert thread repair kits are approved by leading automotive manufactures. Time-Sert easily repairs stripped threads in cylinder head bolts, spark plug holes and oil drain pans as well. Many thread repair kits are available for your threaded bushing application in metric and american sizes. Time-Sert is the very best in thread repair! Time Sert 0561 thread repair kits are made in the United States. Time Sert 0561 Kit Contains: Drill, Counterbore, Tap, Installation Driver, (5) Steel Inserts - Part # 05611