14k nib unit size 5. ABS plastic feeder and housing.
Size 5, that means that the feeder is 5 millimeters in diameter. Thread housing M6.4x0.5, a drawing with dimensions can be found in the las picture of the gallery in this product.
Customized breather holes are hand cut.
Regrinds are not recommended with semi-flex.
We do offer a tip regrinding service for your selected nib. To know more about hem click HERE.