Section 20820 Of Article 6. Undetectable Knife From California Penal Code >> Division 5. >> Title 3. >> Part 6. >> Chapter 2. >> Article 6.

. Section 20810 does not apply to the manufacture or importation of any undetectable knife for sale to a federal, state, or local historical society, museum, or institutional collection that is open to the public, provided that the undetectable knife is properly housed and secured from unauthorized handling, nor does Section 20810 apply to the subsequent sale of the knife to any of these entities.