Edited sentence: A related product is a shield to protect mobile phone users from the "nasty rays" their mobile emits.Of course all that it does is reduce the effective gain of the antenna so the phone uses higher power to compensate, so the battery goes flat quicker.Some people may say this is a good thing because it is less likely that one of these people could have anything of interest/value to say.The perception of "mind control rays" or other invasive mental activity is very real , and such persons have been known to make and wear improvised defences against the invasion