If you've upgraded your LS 1,2,6 or 7 with a powerful Atomic AirForce intake manifold and have ever had the need to pull it off, chances are you'll need new O-rings to ensure a leak free reinstallation.
MSD part number 2716 is a replacement O-ring kit that fits Atomic AirForce Manifolds part number 2701 and 2702.
The kit comes with 10 Viton O-rings that go around the bolts that hold the manifold to the cylinder head.