Non-Metallic Floor Box for Concrete Pour, with 3/4 and 1 in. Hubs. RACO® Nonmetallic floor box has been engineered from the inside out with features that reduce installation time and offer increased capabilities from one box in power, voice and data. Hubbell® nonmetallic floor boxes are economical to install and easy to level off. A wide choice of cover materials and finishes are available. 3 in. minimum pour depth.