The 72 Utility Knife

Do not discard the last part of the – Snap off blades 18mm – or any three of its parts.
This is a special design for the last part, slightly larger than before, with the same familiar clicking sound.
Don't forget filings of moving area and a drop of oil. See the assembly picture. Thank you.

72 = Total length of blade holder

Update... There was a missing file, which I have added. My apologies... and thanks to everyone who pointed this out.