During the summer of 2007 we remade all of the molds for our needles and in that process changed the sizing from the Boye standard of the 1970s to a more current, millimeter based system. The sizes that changed were the #9’s through the #11’s. Those four sizes all grew slightly; all the other sizes stayed the same.
Consequently, we also resized the cases at the same time. It’s a small difference, and new parts fit in old cases and visa versa, but please be aware that newer needles will fit tightly in old cases and older needles will fit loosely in new cases.
If you’re looking to replace an old case, we currently have a good supply of them left in blue. The blue cases are available in either new or old sizing, but the pink cases are available only in the new sizing. The new cases can be told apart from the old cases by the “mm” sizes that are stamped on the white inner tray. The old cases have only “US” size stamps. The newly resized ones have both “US” and “mm” size stamps.
Please contact us if you have any further questions.