This is a vintage cut corner square wire frame for making a tailored soft bodied lampshade. 
Base 16” diameter (
Height 13”
Top diameter 8”
Duplex fitting (for use with shade carrier which isn’t included). Pictured on an 5” carrier but I would suggest an 8” carrier.
Note that this is a vintage but unused frame. It does have some scuffs etc but no flaking or rusting.