The M509 are a size larger than the M409 as you can see in the pictures. You can also Google these and see they are top tier.
If you need smaller and closer precision, check out my Five Star USA made cutter listings.If you need more precision than these, maybe best to pay more and buy new ones.
Once you start using high end cutters you may never go back. Most of us would never pay the new retail price but ebay has opened up the world of inexpensive used.
Note: The PVC covers shown are not a factory item but I often use them to make the cutters more compact for shipping. Just letting you know up front if yours come without or with a different cap.
Thanks for your business!