Those cases are usually based on more than the fact that the manufacturer (or in this case the better analogy is a gun store) created (or sold) the actual gun.

Those cases are usually based on more than the fact that the manufacturer (or in this case the better analogy is a gun store) created (or sold) the actual gun. For instance I can think of one case where the makers of the Tek-9 were sued using the fact that they advertised that it had a "fingerprint resistant surface."