Big-Sert 5212 M12X1.25MM Oversized Metric Thread Repair Kit 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 5212 thread repair kits are made in the United States. Big Sert 5212 Kit Contains: Drill, Counterbore, Tap, Installation Driver, (5) Steel Inserts.