E-collars can be very damaging, not only physically, but emotionally and mentally as well and can be very detrimental to your relationship with your dog, just like all and other aversive training methods. These types of collars can also instigate other behavioural issues as they are not designed to help you address the root of the issue, but rather suppress it and mask it temporarily.
Instead of any kind of shock collar, consider using either a flat collar or a harness, as well as the support of a positive reinforcement training to instead work on guiding your dog towards success in a fun, encouraging and harm-free way that will ensure your dog never feels any kind of pain or frustration.