The QL 327 was produced between 1916 and 1920, it used the new Q99 generator wich enabled the lantern to be preheated by two matches on the side of the generator loop, QL stands for Quick-Lite. from 1918 the lantern was renamed the Quick-Lite LQ 327, but still retained the old base rest that has the imprint Air-O-lantern QL until 1921, when the new base rest came along that says Coleman Quick-Lite. The lanter did not use an air baffle until 1920. this particular one was made in 1919, and that is easy to determend as in 1919 the burner caps was of an one year design.