For what it is, it's pretty good. I like the metal case, the ground wire. Decent build quality inside. The description is not very detailed - but it does mention the gas tubes. (update: The description now includes _much_ more information!) It does not mention there are no diodes. But it is quite a bit less money than a L-Com with diodes and gas tubes, so if you feel your situation doesn't warrant the additional money for the two-layer protection - then this could be just what you need.