Wedge French horn screw rims are available with "Giardinelli" 750-36 threads or "Metric" 800-36 threads. Available materials are silver plated brass or Delrin plastic. Delrin are relatively darker than brass. Delrin rims feel less slippery than other materials.
Plastic $90
Silver Plated Brass $120
IMPORTANT NOTE ABOUT PHC 23a CUPS:
Some 23a cups were made with extra thick silver plate, which made the threads slightly oversize. Please indicate in your order if you are using a PHC 23a cup.