All you need is a phone line! All phone lines have a constant flow of voltage, around 40-70 volts (up to 100 volts when it rings!), but you can't just plug stuff into it and expect it to work.
Children older than 5 and more than 40 pounds must ride in a booster seat until the child is 8 years old or is taller than 4 feet 9 inches. Anyone over the age of 8 must be protected by a safety belt.
Children should stay in a booster seat until they are taller than 4 feet 9 inches and weigh more than 80 pounds. Check the fit of a seat belt â correctly positioned, the lap belt should sit across the upper thighs, not the stomach, and the shoulder belt should cross the chest, not the neck.