We have personally field tested this shield material (by personally, we mean our office intern, Justin, has personally tested it...) and we (Justin) found it to be totally resistant to positron beams, 80% resistant to stray gravitron radiation, and slightly impervious to random neutrinos, but that's pretty good considering neutrinos go through lead like it is wet tissue paper. Which is good, because if you get a bunch of anti-matter hurtling at you it makes a pretty big explosion if it touches any of the electrons involved in your ship's hull or, god forbid, your family jewels!
