Nechville banjos have a neck attachment system that uses a device known as the Flux Capacitor. The neck has a hole in the heel that accomodates the brass tube seen in this photo. This brass tube is threaded onto a screw that attaches to the Heli-Mount frame and the neck and tube mechanism are held together by means of a screw inthe heel of the neck. In this photograph, the brass tube has been turned to show the threads of the screw underneath. We can also see the curve of the Heli-Mount Frame that matches the curve of the Nechville neck. The Nechville Musical Products Company is located in Bloomington, Minnesota and is owned and operated by Tom Nechville.