The Once Light is a single lit sphere of handblown Czech glass that rests atop a brass ring (included). Available in three sizes. The 4.5"/110mm and 7"/180mm glass diffusers are available in both "dipped" glass, featuring the SkLO double-dipped flame-polished mouth and "textured" glass, featuring a soft, frosted finish and subtle sculpted vertical ridges. The 10"/250mm diffuser is available in “dipped” glass only.