Building materials not of metal, namely, plastic pipe supports, drainage conduit manhole rings made of precast concrete including a plastic element; building materials made of plastics, namely, landscape edgings and drainage conduit; rigid pipes not of metal for building purposes; drain pipes not of metal; manhole base liners not of metal; manhole covers, namely, manhole base covers not of metal; connection bells not of metal, namely, drain traps for attachment to sewer pipes; infiltration ch...