Different size mouthpieces are available for the bagpipe. The length of the blowpipe on your pipes can be changed without having to buy a new blowpipe. These mouthpieces are made of Delrin, so they are strong and durable. They will fit on most blowpipes. 5 sizes in total are available 2 1/2″, 3″, 4″, 5″, 6″. A proper fitting blowpipe is key to good piping posture.