Mo. Rev. Stat. § 196.331

Eggs shall not be sold to consumers, from bulk lots without displaying a plainly legible sign or placard conspicuously placed and posted in such a position as to clearly and accurately identify the eggs designated thereby, marked with the full, correct and unabbreviated designation of quality and size of such eggs in boldface type letters not less than one inch in height, according to the standards established by the director.