Specifications: The JD-6000 6 in. round meter boxes and lids are injection molded of UV Stabilized Polypropylene. The 6 in. round body is tapered and has a minimum wall thickness of 0.1875 in. The body has a double wall at the top cover seat area with a minimum thickness of 0.13 in. The bottom of the body has a 0.250 in. flange. The 6 in. round lid has an average thickness of 0.218 in.