The ToneGard is made of a light steel “sunrise-pattern” framework coated with a durable black paint with leather & rubber pads at key contact points to protect the instrument. Fits most traditional A & F model mandolins. Among the many satisfied Tone-Gard users include David Grisman and Ricky Skaggs. Tone gards are not recommended for varnish finishes. The rubber pads can leave marks in the finish.