These Vintage opalescent glass bowl shaped shades with drop in fitter , were very popular in the 1930s and 40s . on certain chandeliers , and wall sconces . The shade would drop between the socket , and the wall of the socket cup , and the bulb would be installed to help hold it in place . These Monax shades are not the more familiar petalware but rather have a swirled beaded rib pattern and scalloped top edge . The Shade Measures 6 inches in diameter , stands 2 3/4 inches tall and has a 1 5/8 inch shank style fitter . Free of chips or cracks , these are In wonderful condition for the age of these vintage lamp parts .