See Littelfuse Commercial Vehicle Products Products
Furniture Feed Cover - 8 Inch Flange Diameter - 1 Inch and 1-1/2 Inch Threaded Plugs - Solid Brass with Brushed Finish - For Flush Service Round Floor Box - 140 Cubic Inches - Opening Diameter 5-31/32 Inches - Base Diameter 8-1/8 Inches - Depth 6 Inches - 1 Inch and 1-1/2 Inch Conduit Hubs - Non-Metallic - Minimum Concrete Depth Flush 4 Inches Furniture Feed 3-1/2 Inches.