TexasCHLforum.com

Ghost guns refer to the 80% kits that are sold online. The lower receiver is only milled out to 80% completion. You have to finish the lower by drilling holes and removing material. These are available for both rifles and pistols.

A lower receiver that is completely milled but you add the trigger assembly, grip, bolt stop, etc. are complete lowers and are serial numbered and require a background check to purchase from a FFL.