This Whip-O-Lite shade is No. 309-variegated from 1941. It was designed for use on Aladdin table, hanging, and bracket lamps. I once owned this shade many years ago and traded it off. Years later as my interest grew I regretted having done so and I began hunting for one to replace it. It took almost 20 years to re-acquire this one!
I had to light this one up for you to show you why I regretted trading it off. Before I traded it, I displayed the shade in the display room of the Aladdin Knights at their national gathering in Omaha, Nebraska the summer of 2000. I believe it was on a green moonstone Florentine vase lamp.