Passenger side Y-pipe gasket that connects to the exhaust manifold on the Silverado 1500 5.3L 2wd. On the driver's side it's Fel-Pro part number 61074. No leaks when tightened to 11 ft lbs, I believe the 2nd pass was to 18 ft lbs. I didn't do a second pass, but if I have a leak I will.