The nylon clarinet pins on left hand B and C# are a notorious weak point on newer Buffet clarinets. They are prone to breakage, usually at the worst time, and as the nylon ages it becomes even more brittle.
These carbon fiber clarinet pins are handmade to the exact size and shape of the nylon pins they replace. Carbon fiber is extremely light, so the clarinet will feel exactly the same as before. However, because carbon fiber is up to six times stronger than steel there is no worry of ever breaking one of these pins. They will last the life of the clarinet, guaranteed.