Medical devices, namely, electrical stimulation devices for stimulating nerves or neural tissues for medical purposes; electrical stimulation devices for sacral neuromodulation for medical purposes; medical system for sacral neurostimulation to treat bladder and bowel disorders comprised of an electrical neuromodulation device, stimulation leads, stimulation electrical cables, a patient remote control for the electrical device, and related embedded software that allows for communication between the remote control and the neuromodulation device; a rechargeable electrical stimulation device for stimulating nerves or neural tissue for medical purposes, and a charging system comprised of a battery charging device, a power supply, a charging station for the rechargeable battery and a wearable belt for medical purposes, sold as a unit.