Wow, why is everybody about not learning about e-collars? and the rufus post??? that story is well know, it was an invisible fence collar, it was never turned on and the guy left it on for days on end in the rain, the dog got necrosis, the vet was a friend of the owners from school, she recommended the invisible fence collar.
When Rufus developed Necrosis from the pressure on his neck from the contact points, due to leaving the collar on for days on end, she wrote him the letter which was only for the store he got it from and she was trying to help her one time school friend to get him a refund, she had no idea her letter would end up on the net.
She (no vet) was not qualified to confirm burning and then when trouble started for her she changed her story to acid burns due to battery leakage because the collar he been out in the rain for days, shortly after that she chaged her story again to say she could not confirm any burning.
But, it was his fault for leaving the collar on all the time, it was never even turned on for use and never used as an e-collar invisible fence, and the vet, well she uses an e-collar herself and recommends them to her clients, so that's the real story of Rufus, haven't seen the story misused for a couple of years cause its so well known till now, as usual no mention here that the vet herself uses e-collars and recommends them to her clients.

Its a very old story everyone knows the truth, it means that of the many millions of these collars sold over many years one person did not follow the instructions not to leave them on for long periods and his the dog got nercrosis (bed sores), it sounded like he left the dog outside quite a lot one in many millions is not a problem, it points to the safety of the collars compared to other things in terms of the millions sold and that one user error case of leaving the collar on for a very prolongued period against manufacturers instructions in donkeys years.