All single packs of cigarettes, and electronic cigarettes, and alternative nicotine products must be sold from behind the counter or in an age restricted area or in a sealed display case. Any other tobacco products must be sold in line of sight.
     The restrictions described in this Section do not apply to a retail tobacco store that (i) derives at least 90% of its revenue from tobacco and tobacco related products; (ii) does not permit persons under the age of 21 to enter the premises unless accompanied by a parent or legal guardian; and (iii) posts a sign on the main entrance way stating that persons under the age of 21 are prohibited from entering unless accompanied by a parent or legal guardian.