Detail 01
17.20mm (.677") cup diameter
Matches the 16C4 rim, so switching from trumpet to flugel mid-set does not change where your lips sit.

Independent shopping perspective
Schilke 16F4 flugelhorn mouthpiece in gold, 17.20mm cup. For the trumpet player who wants a flugel piece matching a 16C4 rim feel.

Strong match
Consider the trade-offs
What matters in use
Catalog numbers tell only part of the story. These are the details most likely to change how this product feels, sounds, or fits into a setup.
Detail 01
Matches the 16C4 rim, so switching from trumpet to flugel mid-set does not change where your lips sit.
Detail 02
Shared across the whole F series. Consistent blowing resistance whichever diameter you pick, so choose on rim alone.
Detail 03
Deep conical cup cut for flugelhorn, which is where the dark round tone comes from rather than the horn alone.
Detail 04
Semi-flat with a wider bearing surface. Spreads pressure over more lip, which helps endurance on long sets.
Detail 05
Smoother and warmer against the lip than silver, and the usual choice for players who react to silver.
Final check
Product questions
Straight answers to the questions shoppers most often ask about this product.
The series is cut to match: 13F4 to a 13A4a, 14F4 to a 14A4a, 16F4 to a 16C4, 17F to a 17, 18F to an 18, 20F to a 20.
No. The flugelhorn shank and the deep conical cup are specific to flugel. Use a trumpet mouthpiece in a trumpet.
The 15F is 17.12mm with a rounder standard rim; the 16F4 is 17.20mm with the wider semi-flat number 4 rim. Similar diameter, different bearing surface.
Flugelhorn receivers are not fully standardized across makers. Check what taper your horn takes before ordering.
Reference
The complete catalog record, organized around the decisions musicians make when comparing gear.