A thin strip of material that attaches to the Instrument's mouthpiece and vibrates to produce a sound. They come in different strengths, designated by a number 1-5. The higher the number, the stiffer the reed. Stiffer reeds produce darker and more preferable sounds, but require proficiency to use. Beginner Clarinet and Saxophone players generally start out with “strength: 2” reeds and typically go through several of these when first starting out; so we suggest starting with a box of 10.