Shanghai the Guerlain Electrical Material Co., Ltd.: T shaped seized mouth corrosion-resistant, high impact strength, fluid resistance is small, compared to the same kind of caliber of cast iron traffic increase 30% 2 T-shaped seized mouth anti-aging, long service life, construction of drainage and sewage 3 T-shaped ideal material seized mouth lightweight and durable, easy to install, can effectively speed up the progress of the project, and to reduce the construction cost of four T-shaped inspection port saving construction costs, relative to the same specifications traditional cast iron pipe, can greatly reduce the cost The inspection hatchway (checkhole, checkpipe) is with an openable inspection cover short tube, fitted in the drainage risers and longer on the horizontal section of pipe, for the check and cleared through use. Examination of the mouth is the transport of foreign trade at the set card haulage container must pass through and out of the container terminal, container terminal box exchange with drag boxes, document processing, and information recording an important business sector!