Stam keilim ainum b'nei yoman (סתם כלים אינם בני יומן):

• Basic halacha;


• Kashering;


• Pesach;


• Factories.

See seforim by Rabbi Cohen at ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠www.kashrushalacha.com