West Virginia on Wednesday spearheaded a coalition of 27 Republican-led states urging the Supreme Court to limit the Biden administration’s so-called ghost guns ban, which also classifies certain weapons parts as firearms.

The “Frame or Receiver” rule, established by the Bureau of Alcohol, Tobacco, Firearms and Explosives in 2022, expanded the definition of a “firearm” to include weapon parts kits that can be assembled into functional firearms, as well as partially complete or disassembled frames or receivers. The nine justices will hear arguments in Garland v. VanDerStok on Oct. 8, one of the first cases they will hear when their new term begins this fall.