Low-tech propellers are a type of propulsion system that uses OARS, which are four-letter paddles used to move a boat through the water. OARS are a simple and effective way to propel a boat, and have been used for centuries. They are still used today in some areas, such as rowing competitions and recreational boating. Low-tech propellers are a great option for those who want to enjoy the outdoors without relying on modern technology.