Abstract: A stringed musical instrument having a body and a neck extending outwardly therefrom and a support frame having at least one lateral or side arm secured to the body of the instrument with the arm being selectively adjustable and extensible such that when a shoulder strap is attached between the instrument and the selectively adjustable arm, the support of the strap may be selectively varied about the neck of the player and the balance of the instrument may be changed in correspondence with the change in the center of gravity effected by the variation in the extension of the arm.