Vandoren M/O Clarinet Ligature (Black)The new ligature combines the lightness of the legendary Masters ligature and the clamping efficiency of the OPTIMUM ligature. Lightweight. Easy to set up. Quick and symmetrical tightening with a unique double track screw mechanism. Inverted tightening with only 2 small contact points on the reed. the M O ligature allows an optimum vibration of the reed and a crisp articulation.