Nechville banjos have a unique system called the Heli-Mount system. With this system, one adjusts head tension by turning an internal ring inside the Heli-Mount frame which uniformly tightens or loosens the tension on the head. The wrenches in this photograph are used to turn that internal ring. The Nechville Musical Products Company is located in Bloomington, Minnesota and is owned and operated by Tom Nechville.