Great set of hearing aids these were made for sever hearing loss on right side but don’t see why can’t be reversed to sever loss on left side how these work is they take sound from left side and sends it to the right side the left side can also be adjusted to increase or decrease sound level comes with charger different power level speaker travel case manual and more welcome to try them before buying them they were very expensive new and hold charge for the whole day no batteries to buy or change