Hi Geoffrey,

Thank you for asking. These are the names of the separate nibs currently supplied by Bortoletti, which are sold separately in my store as well:

1. Number 5 Myers
2. Heintze & Blanckertz 1107EF
3. Gobbina 055EF
4. Penna Signorina 0.47ef
5. Penna Cavallo 1898 EF
6. Perry & Co 104 EF
7. Penna Gorizia No. 127
8. Kantel No. 920 EF
9. Schuler R.T. 530EF
10. Presbitero 601FF
11. Elettra No. 7
12. Gloria N. 400/2

https://calligraphyartsuk.com/en-gb/54-nibs-holders-reservoirs?manufacturer-=bortoletti

Do let me know if you have any other questions.

Many thanks,

Jane