There are several type of Class 3 items that are restricted by the National Firearms Act.
Each state can impose additional restrictions on the sale, purchase, and transfer of class 3 firearms in addition to the compliance that is required with the national Firearms Act.
In Michigan you can own the following items that are regulated the the National Firearms Act
Machine GunsIn Michigan you cannot own the following NFA restricted items.
Any Other Weapon (AOW)
Destructive Devices (DD)
Short Barreled Shotguns (SBS) * Only some may be owned
Short Barreled Rifles (SBR) * Only some may be owned
and some AOW's like Tasers or Stun Guns by private citizens whether or not they are class 3 items or the individual has a CCW permit
Follow this link to find out more about Michigan and NFA restrictions on Class 3 Firearms