The Opus 88 #10 Nib Unit is the branding used by Opus 88 for its JoWo #5 sized stainless steel screw-in nib units. These units are specifically designed for the...

The Opus 88 #12 Nib Unit is the branding used by Opus 88 for its JoWo #6 sized stainless steel screw-in nib units. The replacement steel nib Opus 88 #6...