GR Type Conduit Outlet Box, Explosion-Proof, Dust-Ignitionproof, Malleable Iron, Unilet, GRX Hub Type. Includes: Internal Ground Screw and O-Ring, Internally Threaded Surface Cover with 3.88" Opening, 18 Cubic Inches and (4) 1" Threaded Hubs. For use with Threaded Metal Conduit
- Material: Malleable Iron
- Diameter: 1 in
- Cubic Inches: 18 in³