The Pierobon Flugelhorn top has the same rim as the regular Pierobon Deep Flugelhorn top and the Pierobon Classic trumpet mouthpiece.
The ID is .661 with an OD of 1.12. The rim is a very comfortable Gabriel style with a lateral dip of 15/1000".
The cup is medium deep for a flugel mouthpiece with a DOC design and the throat is .169". This is a great all round, medium sizes flugel mouthpiece.
This top must be used with a special flugelhorn shank for Bach, Yamaha (Standard), or French receivers. It can also be used with a special trumpet or cornet shank. Shanks are available HERE