Standard Series Mouthpieces
Numbering system explained.  Example XX-29C4
First numbers (29) Rim inner diameter (29-35) Larger number is a larger diameter
Letter (C) Cup Shape (B-D). B- V shaped cup; C- U shaped cup; D- Double cup
Last number (4) rim contour (1-4) 1 Round, 3 standard, 5 flat).
 
 
HR-29B-17.07mm ID; 3.90mm bore.  Fairly thick rim with a relatively small inner diameter for superior high tone. Medium throat for easy all-around playing.
HR-29C4-17.08mm ID; 3.98mm bore.  Ideal for Bb/HF horns. Relatively sharp shoulder and medium throat for clear tone.
HR-30B-17.27mm ID; 3.90mm bore.  Standard “V” cup model with a larger inner rim diameter than the 29B. Smooth airflow. Ideally matches horns with a very narrow bell.
HR-30C4-17.28mm ID; 3.98mm bore.  Medium inner rim diameter and “U” cup for fast response. Standard type with ideal resistance and powerful, rich tone.
HR-30D4-17.08mm ID; 4.50mm bore.  Exceptionally rich tone. Matches horns with a wide bell. Excellent stability on high notes.
HR-31B- 17.47mm ID; 3.90mm bore.  Medium inner rim diameter with a “V” cup for a “traditional” soft horn tone. High volume over a wide range. A good match for horns with a narrow bell.
HR-31D4-17.28mm ID; 4.50mm bore.  Heavy tone and high volume. Relatively flat rim of medium thickness for easy playability.
HR-32B-17.67mm ID; 3.90mm bore.  Large inner rim diameter for outstanding lownote tone. Largest “V” cup in the lineup. Rich, mellow tone.
HR-32C4-17.48mm ID; 3.98mm bore.  Plenty of volume. Relatively flat rim of medium thickness for easy playability.
HR-32D4-17.48mm ID; 4.50mm bore.  Largest double-cup in the lineup. Also ideal for Wagnerian tuba. Large cup volume for a dark, heavy sound and easy low notes.
HR-34C4-17.88mm ID; 3.98mm bore.  Plenty of volume. “U” cup for powerful performance.
HR-35C4-18.08mm ID; 3.98mm bore.  Largest “U” cup in the lineup. Can deliver a heavy sound. Suitable for large orchestras.