Multi pipe reducers are designed for use as reducers when connecting two waste water pipes with different outer and inner diameters, as well as waste water pipes with the same or different materials and surface structure. The mutli pipe reducer has six dimension combinations and can be combined with other pipe reducers. Multi pipe reducers are suitable for vertical and horizontal installation. They are easy to install and do not require any tools as they have perforated breakpoints, and are approved for concealed placement.