Bois Ring Ligature and Cap for Bb Clarinet Mouthpieces. A unique ligature design from Bois which frees the sound by allowing the reed to freely vibrate. Stable but versatile and unbelievably easy to use. Simple Slip on and off fitting Made of Indestructible Delrin material Will not dampen natural mouthpiece vibrations No tightening screws to loose or break Interior ring offers 3 point minimal contact Soft contact points with the reeds Unique design prevents slipping Very Free blowing Precision made in the USA